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U.  S.  DEPARTMENT  OF  AGRICULTURE 

BUREAU  OF  ENTOMOLOGY— BULLETIN  NO.  64. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK- 
OF  THE  RUREAU  OF  ENTOMOLOGY— IX. 


CONTENTS  AND  INDEX. 


Issued  January  27,  1911. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1911. 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  NO.  64. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  RUREAU  OF  ENTOMOLOGY— IX. 


I.  THE  MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 

By  A.  W.  MORRILL,  Special  Field  Agent. 

II.  NOTES  ON  THE  ECONOMIC  IMPORTANCE  OF  SOWBUGS. 

By  W.  DWIGHT  PIERCE,  Special  Field  Agent. 

HI.  NOTES  ON  “ PUNKIES.” 

By  F.  C.  PRATT,  Special  Field  Agent. 

IY.  AN  INJURIOUS  NORTH  AMERICAN  SPECIES  OF  APION, 
WITH  NOTES  ON  RELATED  FORMS, 

By  F.  H.  CHITTENDEN,  Entomologist  in  Charge  of  Breeding  Experiments. 

Y.  INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS, 

By  F.  H.  CHITTENDEN,  Entomologist  in  Charge  of  Breeding  Experiments. 

Y I.  THE  GREENHOUSE  THRIPS. 

By  H.  M.  RUSSELL,  Agent  and  Expert. 

VII.  NEW  BREEDING  RECORDS  OF  THE  COFFEE-BEAN  WEEVIL, 

By  E.  S.  TUCKER,  Special  Field  Agent. 

VIII.  THE  WOOLLY  WHITE-FLY:  A NEW  ENEMY  OF  THE 
FLORIDA  ORANGE. 

By  E.  A.  BACK,  Agent  and  Expert. 

IX.  NOTES  ON  A COLORADO  ANT. 

By  H.  O.  MARSH,  Agent  and  Expert. 

X.  THE  PECAN  CIGAR  CASE-BEARER, 

By  H.  M.  RUSSELL,  Agent  and  Expert. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1911. 


B UREA  U OF  ENTOMOLOGY. 


L.  O.  Howard,  Entomologist  and  Chief  of  Bureau. 

C.  L.  Marlatt,  Assistant  Entomologist  and  Acting  Chief  in  Absence  of  Chief. 
R.  S.  Clifton,  Executive  Assistant. 

W.  F.  Tastet,  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truck  crop  and  stored  product  insect  investigations. 
A.  D.  Hopkins,  in  charge  of  forest  insect  investigations . 

W.  D.  Hunter,  in  charge  of  southern  field  crop  insect  investigations. 

F.  M.  Webster,  in  charge  of  cereal  and  forage  insect  investigations. 

A.  L.  Quaintance,  in  charge  of  deciduous  fruit  insect  investigations. 

E.  F.  Phillips,  in  charge  of  bee  culture. 

D.  M.  Rogers,  in  charge  of  preventing  spread  of  moths,  field  work. 

Rolla  P.  Currie,  in  charge  of  editorial  work. 

Mabel  Colcord,  librarian. 


ii 


LETTER  OF  TRANSMITTAL. 


U.  S.  Department  of  Agriculture, 

Bureau  of  Entomology, 
Washington , D.  C.,  November  30,  1910. 
Sir  : I have  the  honor  to  transmit  herewith  ten  papers  on  miscella- 
neous insects  for  publication  as  Bulletin  No.  64  and  as  No.  IX  of  the 
series  of  bulletins  entitled  “Some  Miscellaneous  Results  of  the  Work 
of  the  Bureau  of  Entomology. 7 7 These  papers,  which  were  issued 
separately  during  1907,  1908,  1909,  and  1910,  are  as  follows:  The 
Mexican  Conchuela  in  Western  Texas  in  1905,  by  A.  W.  Morrill; 
Notes  on  the  Economic  Importance  of  Sowbugs,  by  W.  Dwight  Pierce ; 
Notes  on  “Punkies,”  by  F.  C.  Pratt;  An  Injurious  North  American 
Species  of  Apion,  with  Notes  on  Related  Forms,  by  F.  H.  Chittenden; 
Insects  Injurious  to  the  Loco  Weeds,  by  F.  H.  Chittenden;  The 
Greenhouse  Thrips,  by  II.  M.  Russell;  New  Breeding  Records  of  the 
Coffee-bean  Weevil,  by  E.  S.  Tucker;  The  Woolly  White-fly,  by  E.  A. 
Back;  Notes  on  a Colorado  Ant,  by  H.  O.  Marsh;  the  Pecan  Cigar 
Case-bearer,  by  H.  M.  Russell. 

Respectfully,  L.  O.  Howard, 

Entomologist  and  Chief  of  Bureau. 

Hon.  James  Wilson, 

Secretary  of  Agriculture. 


in 


PREFACE. 


The  present  publication  comprises  ten  articles  previously  pub- 
lished separately  as  parts  and  now  brought  together  to  form  the 
complete  bulletin,  which  is  No.  IX  of  the  series  entitled  “Some 
Miscellaneous  Results  of  the  Work  of  the  Bureau  of  Entomology.  ” 
The  previous  bulletins  of  this  series  are  Nos.  7,  10,  18,  22,  30,  38,  44, 
and  54.  The  articles  of  the  present  bulletin  relate  to  species  which, 
although  economically  important,  do  not  properly  come  under  the 
scope  of  any  of  the  other  bulletins  thus  far  published  in  parts,  viz, 
those  relating  to  forest  insects,  the  cotton  boll  weevil  and  related 
and  associated  insects,  truck-crop  insects,  deciduous  fruit  insects, 
cereal  and  forage  insects,  and  apiculture.  The  investigations  the 
results  of  which  are  here  published  were,  however,  conducted  coin- 
cidently  with  the  various  projects  of  several  branches  of  the  Bureau, 
including  those  dealing  with  some  of  the  groups  of  insects  men- 
tioned above. 

The  first  paper  treats  of  the  Mexican  conchuela,  a species  inves- 
tigated in  Mexico  in  1904,  at  which  time  it  had  not  yet  been  reported 
to  entomologists  as  of  economic  importance  in  the  United  States. 
It  was  predicted  at  that  time  that  should  the  pest  become  abundant 
in  Texas  it  would  cause  considerable  damage  to  crops.  The  results 
of  investigations  in  Texas  in  1905  confirmed  the  prophecies  of  1904. 

Part  II  presents  economic  notes  on  three  common  species  of  sow- 
bugs  encountered  during  field-crop  investigations  in  Texas  and  other 
parts  of  the  South,  while  Part  III,  by  F.  C.  Pratt,  treats  of  the 
biologies  of  the  various  biting  flies  belonging  to  the  genus  Ceratopogon, 
known  commonly  as  “punkies.” 

Part  IV  treats  of  a small  weevil  ( Apion  griseum  Sm.)  injurious  to 
beans  in  Texas  and  New  Mexico  and  includes  biologic  notes  on  a 
number  of  related  forms. 

Part  V considers  a number  of  the  more  important  insects  which 
feed  upon  the  loco  weeds.  This  investigation  was  undertaken  in 
cooperation  with  the  loco-weed  investigations  of  the  Bureau  of 
Plant  Industry,  and  as  it  was  conclusively  shown  that  insects  of 
several  species  were  largely  responsible  for  control  of  the  plant  on 
prairies  and  grass  lands  a publication  covering  these  insects  was 
deemed  desirable. 


VI 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Part  VI  considers  the  greenhouse  thrips  ( Heliothrips  Jisemor- 
rhoidalis  Bouche),  a species  previously  recorded  as  injurious  to 
a number  of  hothouse  plants.  This  insect  was  found  injuring  mango, 
crotons,  and  other  plants  on  beds  and  in  parks  at  Miami,  Fla.  The 
results  of  a series  of  experiments  for  its  control  are  given  in  this 
number. 

Part  VII  is  largely  supplemental  to  an  article  in  Bulletin  No.  8 
of  the  Division  of  Entomology,  giving  a note  on  new  food  materials 
for  the  coffee-bean  weevil  ( Arxcerus  fasciculatus  DeG.).  This 
insect  was  discovered  working  in  chinaberries  and  cornstalks  adja- 
cent to  cotton  fields  during  an  investigation  of  cotton  insects. 

A new  and  dangerous  species  of  Aleyrodes  attacking  citrus  fruits 
is  the  subject  of  Part  VIII.  This  species  (. Aleyrodes  howardi  Quaint.), 
which  occurs  on  several  islands  of  the  West  Indies,  including  Cuba 
and  Porto  Rico,  has  recently  made  its  appearance  in  Florida.  Present 
indications  are  that  this  species  will  be  controllable  by  the  same 
measures  used  for  the  citrus  white  fly,  which  it  much  resembles  in 
capacity  for  damage. 

Part  IX  gives  the  results  of  experiments  undertaken  for  the  con- 
trol of  a species  of  ant  ( Formica  cinereorufibarbis  Forel),  which  fosters 
the  melon  aphis  in  Colorado,  protecting  it  largely  from  predaceous 
enemies.  The  control  of  this  ant  may  prove  of  great  value  as  a 
measure  against  the  melon  aphis. 

Part  X is  a biologic  account  of  a.  minor  pecan  pest,  the  pecan  cigar 
casebearer  in  the  South,  and  includes  suggestions  for  its  control. 


CONTENTS 


Page. 

The  Mexican  conchuela  ( Pentatoma  ligata  Say)  in  western  Texas  in  1905, 

A.  W.  Morrill..  1 

An  associated  species 2 

General  agricultural  conditions  at  Barstow,  Tex 2 

Damage  to  crops  previous  to  1905 i 2 

Crops  damaged  in  1905 3 

Other  food  plants 8 

Seasonal  history 8 

Natural  enemies 9 

Methods  of  control 11 

Notes  on  the  economic  importance  of  sowbugs W.  Dwight  Pierce..  15 

Armadillidium  vulgare  Latr 15 

Porcellio  laevis  Latr 21 

Metoponorthus  pruinosus  Brandt - 22 

Conclusions 22 

Notes  on  “Punkies”  ( Ceratopogon  spp.) F.  C.  Pratt..  23 

Ceratopogon  guttipennis 23 

Other  species  of  Ceratopogon . . 26 

Other  blood-sucking  Chironomidae 28 

An  injurious  North  American  species  of  Apion,  with  notes  on  related  forms, 

F.  H.  Chittenden . . 29 

Apion  griseum  Sm 29 

Apion  colon  Sharp 30 

Notes  on  related  forms 31 

Insects  injurious  to  the  loco  weeds F.  H.  Chittenden. . 33 

The  false-indigo  gall-moth  ( Walshia  amorphella  Clem.) 34 

The  loco  root-maggot  ( Pegomya  lupina  Coq.) 35 

The  fickle  midge  ( Sciara  inconstans  Fitch) 36 

The  four-lined  loco  weevil  ( CleonvA  quadrilineatus  Chevr.) 37 

The  yellow  loco  fly  ( Tritoxa  incurva  Loew.) 38 

The  spotted  root  fly  ( Euxesta  notata  Wied.) 38 

The  bur-clover  aphis  ( Aphis  medicaginis  Koch) 40 

The  meal  snout-moth  ( Pyralis  farinalis  L.) 40 

Plant-bugs,  leafhoppers,  etc 41 

Miscellaneous  insects 41 


a The  ten  papers  constituting  this  bulletin  were  issued  in  separate  form  on  April  2, 
1907  (Pts.  I to  III),  January  14  and  May  29,  1908  (Pts.  IV  and  V),  August  4 and  5, 
1909  (Pts.  VI  and  VII),  and  May  7,  October  17,  and  November  12,  1910  (Pts.  VIII 
to  X). 


68045°— Bull.  64—11 2 


VII 


•VIII 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Page. 

The  greenhouse  thrips  ( Heliothrips  hsemorrhoidalis  Bouche) H.  M.  Russell. . 43 

History 43 

Recent  records 44 

Nature  and  extent  of  injuries 44 

Origin  and  distribution 45 

Description 46 

Habits  of  the  adult 48 

Habits  of  the  larvse 49 

Habits  of  the  prepupa  and  pupa 50 

Food  plants 51 

Life  history 51 

Natural  control 52 

Artificial  control 52 

Bibliography 58 

New  breeding  records  of  the  coffee-bean  weevil  ( Arxcerus  fasciculatus  De  Geer), 

E.  S.  Tucker. . 61 

Nature  of  injury  to  corn 61 

Notes  on  life  history  in  corn 63 

Occurrence  in  chinaberries;  parasites 63 

Habits  in  general 64 

The  woolly  white-fly:  A new  enemy  of  the  Florida  orange  ( Aleyrodes  howardi 

Quaintance) E.  A.  Back..  65 

Injury  and  extent  of  infestation 65 

Life  history 66 

Description 68 

Food  plants 70 

Distribution 70 

Natural  enemies 70 

Remedies 71 

Notes  on  a Colorado  ant  ( Formica  cinereorufibarbis  Forel) II.  0.  Marsh. . 73 

Injurious  habits 73 

Experiments  with  potassium  cyanid  as  a remedy 74 

The  pecan  cigar  case-bearer  ( Coleophora  caryse.foliella  Clem . ) II.  M.  Russell. . 79 

Early  history t 79 

Recent  records 80 

Distribution 80 

Food  plants 81 

Character  of  injury 81 

Description 82 

Habits  of  the  adult 83 

Habits  of  the  larva / 84 

Habits  of  the  pupating  larva 85 

Seasonal  history 85 

Recommendations 86 

Bibliography 86 

Index ' 87 


ILLUSTRATIONS, 


PLATES. 

Page. 

Plate  I.  Fig.  1. — Egg  batch  of  Pentatoma  ligata,  showing  hatched  and  un- 
hatched eggs.  Fig.  2. — Egg  batch  of  Pentatoma  ligata  parasitized 

by  Telenomus  ashmeadi 10 

II.  Work  of  Armadillidium  vulgare  on  cotton 16 

III.  Work  of  the  coffee-bean  weevil  ( Arsecerus  fasciculatus ) in  cornstalks.  62 

IV.  The  woolly  white-fly  ( Aleyrodes  howardi  Quaintance)  on  orange. 

Fig.  1.— Moderate  infestation  of  leaf,  showing  many  specimens  in 
larval  instars.  Fig.  2. — Eggs  on  tender  leaf.  Fig.  3. — Heavy 
infestation  of  leaf,  showing  globules  of  honeydew  embedded  in 

woolly  secretions  overgrown  by  fungi 66 

V.  Work  of  the  pecan  cigar  case-bearer  ( Coleophora  carysefoliella) . Fig. 

1. — Twig  of  pecan,  showing  injury  to  foliage.  Fig.  2. — Leaves  of 

pecan,  showing  mines 82 

VI.  Pecan  tree,  showing  foliage  checked  and  injured  by  pecan  cigar 

case-bearer 84 

VII.  Normal  pecan  tree,  same  size  as  that  shown  in  Plq,te  VI,  but  with- 
out injury  by  the  pecan  cigar  case-bearer 84 

TEXT  FIGURES. 

Fig.  1.  The  conchuela  ( Pentatoma  ligata ):  Adult,  egg  mass,  eggs 4 

2.  Telenomus  ashmeadi , an  egg  parasite  of  Pentatoma  ligata 10 

3.  Ceratopogon  guttipennis:  Adult,  larva,  pupa,  details 24 

4.  Ceratopogon  guttipennis:  Mouth  parts  of  adult 24 

5.  Ceratopogon  varicolor:  Pupa 25 

6.  Ceratopogon  stellifer:  Adult 26 

7.  Apion  assimile 30 

8.  The  false-indigo  gall-moth  ( Walshia  amorphella):  Adult,  larva,  work..  34 

9.  The  fickle  midge  ( Sciara  inconstans ):  Adults  and  details,  larva,  pupa. . 37 

10.  The  four-lined  loco  weevil  ( Cleonus  quadrilineatus):  Adult 37 

11.  The  four-lined  loco  weevil  ( Cleonus  quadrilineatus ):  Cocoon 38 

12.  The  spotted  root  fly  ( Euxesta  notata ) : Adult  male  and  female 39 

13.  The  meal  snout-moth  ( Pyralis  farinalis):  Adult,  larva  and  details, 

chrysalis  and  details 40 

14.  Bruchus  obsoletus:  Adult  and  details 41 

15.  The  greenhouse  thrips  ( Heliothrips  hsemorrhoidalis) : Adult  female  and 

antenna 46 

16.  The  greenhouse  thrips:  Egg,  first-stage  larva,  full-grown  larva 47 

17.  The  greenhouse  thrips:  Prepupa,  pupa 48 

18.  The  coffee-bean  weevil  ( Arsecerus  fasciculatus ):  Larva,  adult,  pupa..  62 

19.  The  woolly  white-fly  ( Aleyrodes  howardi ):  Eggs,  female  ovipositing..  67 

20.  The  woolly  white-fly:  Larva,  first  instar... 68 

21.  The  woolly  white-fly:  Details  of  larva  of  second  instar 69 

22.  The  woolly  white-fly:  Pupa  case  and  details 70 

23.  Pecan  twigs  with  buds  and  young  leaves  killed  by  pecan  cigar  case- 

bearer  {Coleophora  carysefoliella) 8i 

24.  The  pecan  cigar  case-bearer  ( Coleophora  caryxfoliella ):  Adult,  larvae  in 

cases 82 


IX 


ERRATA. 


Page  25,  line  11  from  bottom,  for  C.  read  Ceratopogon. 

Page  41,  line  9 from  bottom,  for  virginica  read  virginiana. 

Page  43,  between  lines  4 and  5 insert  ( Heliothrips  hxmorrhoidalis  Bouch6). 
Page  51,  lines  10  and  17,  for  azalia  read  azalea. 

Page  51,  line  11,  for  lauristina  read  laurestina. 

Page  51,  line  17,  for  catleyia  read  cattleya. 

Page  51,  line  17,  for  dendrobuim  read  dendrobium. 

Page  80,  line  12,  for  1893  read  1883. 


x 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 
BUREAU  OF  ENTOMOLOGY  BULLETIN  No.  64,  Part  I. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  MEXICAN  CONCHUELA  IN  WESTERN 
TEXAS  IN  1905. 


A.  W.  MORRILL, 

Special  Field  Agent. 


Issued  April  2,  1907. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1 907. 


CONTENTS. 


Page. 

Introduction 1 

An  associated  species 2 

General  agricultural  conditions  at  Barstow,  Tex 2 

Damage  to  crops  previous  to  1905 2 

Crops  damaged  in  1905 3 

Alfalfa 1 3 

Milo  maize : 5 

Cotton 6 

Beaches 1 G 

Grapes — 7 

Garden  vegetables 7 

Other  food  plants 
Seasonal  history  _ 

Natural  enemies 9 

Egg  parasites 9 

Tachinid  parasites 11 

Predaceous  enemies 11 

Methods  of  control 11 

Avoidance  of  injury  to  the  seed  crop  of  alfalfa 12 

A suggestion  as  to  mechanical  contrivances  for  collecting  the  insects.^  12 

Preventive  and  protective  measures ! 13 

Remedies  when  crops  other  than  alfalfa  are  attacked 14 


1L LUSTRATIONS 


PLATE. 

Page. 

Plate  I.  Fig.  1. — Egg  batch  of  Pentatoma  ligata,  showing  hatched  and 
unhatched  eggs.  Fig.  2. — Egg  batch  of  Pentatoma  ligata 
parasitized  by  Telenomus  ashmeadi 10 

TEXT  FIGURES. 

Fig.  1.  The  eonchuela  (Pentatoma  ligata)  : adult,  egg  mass,  eggs 4 

2.  Telenomus  ashmeadi , an  egg  parasite  of  Pentatoma  ligata 10 


ii 


00  oo 


IT.  S.  D.  A.,  B.  E.  Bull.  64,  Part  I. 


Issued  April  2,  1907. 


SOME  MISCELLANEOUS  RESULTS  0E  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 

( Pentatoma  ligata  Say.)® 

By  A.  W.  Morrill, 

Special  Field  Agent. 

INTRODUCTION. 

In  a recent  bulletin  of  the  Bureau  of  Entomology  h the  writer  gave 
an  account  of  the  Mexican  conchuela  ( Pentatoma  ligata  Say,  fig.  1), 
based  upon  an  investigation  conducted  in  northern  Mexico  in  Septem- 
ber, 1904.  It  was  predicted  that  should  the  pest  ever  become  very 
abundant  in  this  country,  where  more  diversified  farming  is  usually 
practiced,  it  would  be  likely  to  affect  a wide  range  of  farm  crops 
instead  of  confining  its  attacks  to  cotton  alone.  Almost  unknown  in 
1903,  the  conchuela,  as  it  is  called  by  the  natives  of  Mexico,  first  be- 
came of  considerable  importance  as  a cotton  pest  in  the  leading  cotton 
district  of  Mexico — the  “ Laguna  ” — and  in  1904  established  its  repu- 
tation as  an  enemy  of  alfalfa  in  western  Texas  by  ruining  in  specific 
instances  seed  valued  at  over  $1,000,  representing  the  loss  to  the  crops 
of  two  growers  from  whom  definite  reports  were  obtained.  This  loss 
in  western  Texas  was,  however,  first  made  known  to  entomologists  in 
July  of  the  following  year  (1905),  through  correspondence  of  a resi- 
dent of  Barstow,  Tex.,  with  Mr.  W.  D.  Hunter,  in  charge  of  the  inves- 
tigations on  cotton  insects  conducted  by  this  Bureau.  As  the  writer 
was  at  that  time  in  Mexico,  continuing  his  investigations  of  this  pest, 
Mr.  J.  C.  Crawford  was  sent  to  Barstow  to  investigate  the  economic 
status  of  the  insect  there.  His  preliminary  observations  were  made 
on  July  20  to  22,  inclusive,  and  were  followed  by  visits  to  Barstow 
by  the  writer  on  August  11  and  12  and  September  12,  and  by  Mr. 
Crawford  on  October  13  and  November  14.  The  reports  of  Mr. 
Crawford,  which  were  duly  submitted  to  Mr.  Hunter,  have  been 
freely  used  by  the  writer  in  preparing  this  paper. 

® Order  Hemiptera,  family  Pentatomidse. 

& Bui.  54,  Bur.  Ent.,  U.  S.  Dept.  Agric.,  pp.  18-34,  1905. 

1 


2 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


AN  ASSOCIATED  SPECIES. 

An  allied  pentatomid,  the  grain  bug®  ( Pentatoma  sayi  Stal), 
was  found  at  Barstow  associated  with  the  conchuela.  In  1905  this 
species  was  not  plentiful  enough  to  cause  much  damage  to  crops  by 
itself,  but  as  the  character  of  its  injury  and  that  of  the  conchuela  is 
the  same  it  is  necessary  to  consider  the  two  species  together  when  they 
are  found  on  the  same  food  plant.  In  this  case  they  were  found 
together  only  on  alfalfa  and  Milo  maize,  although  the  grain  bug  is 
known  to  have  a wide  range  of  food  plants  and  probably  is  fully  as 
general  in  its  feeding  habits  as  is  the  conchuela.  The  history  of  the 
former  species  as  a pest  antedates,  even  in  western  Texas,  that  of 
the  latter,  for  as  long  ago  as  December,  1895,  specimens  of  Pentatoma 
sayi  were  received  by  this  Bureau  from  Toyahvale,  Beeves  County, 
Tex.,  with  a report  that  they  had  destroyed  40  acres  of  peas  and  2 
acres  of  lima  beans  on  the  correspondent’s  farm.  It  is  interesting  to 
note  that  this  report  came  from  a point  not  50  miles  from  BarstoAv. 
Since  that  time  this  species  lias  earned  a bad  reputation  by  its  de- 
structiveness  to  wheat  and  oats  in  Colorado  and  elsewhere. 

GENERAL  AGRICULTURAL  CONDITIONS  AT  BARSTOW,  TEX. 

Ward  County,  of  Avhich  Barstow  is  the  county  seat,  is  situated  in 
western  Texas,  a short  distance  south  of  the  southeastern  corner  of 
Xeiv  Mexico.  With  the  exception  of  a narrow  valley  along  the  river 
the  country  consists  of  high  rolling  prairie  covered  in  large  part  with 
a short  groivtli  of  mesquite  and  sage.  Being  in  the  arid  region  the 
rainfall  is  too  light  to  be  depended  on  for  agricultural  purposes  and 
all  crops  are  groivn  under  irrigation,  a practice  Avhich  began  Avith  the 
settlement  of  the  county  in  1891.  Water  for  irrigation  is  obtained 
from  the  Pecos  Biver,  and  at  present  about  10,000  acres  are  under 
cultivation  in  the  county.  Of  this  area,  in  1905,  about  5,000  acres 
Avere  deAroted  to  cotton  and  the  greater  part  of  the  remainder  to 
grapes,  peaches,  and  alfalfa.  The  elevation  of  BarstoAv  is  about 
2,500  feet  above  the  sea  level. 

DAMAGE  TO  CROPS  PREVIOUS  TO  1905. 

According  to  residents  of  Barstow  Avho  are  best  informed  concern- 
ing the  conchuela,  the  insect  never,  previous  to  1904,  attacked  crops 
of  any  kind  in  sufficient  numbers  to  attract  attention.  As  far  as 
can  be  learned  there  had  been,  previous  to  that  time,  no  attempt 
to  produce  a seed  crop  of  alfalfa.  The  occurrence  of  this  pest  on 
cotton  in  moderate  numbers  is  not  likely  to  be  associated  with  the 

«In  using  this  common  name  for  this  species  the  writer  follows  Prof.  C.  I*. 
Gillette.  Bui.  94,  Colo.  Exp.  Sta.,  p.  3,  Dec.,  1904. 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


3 


injury  which  usually  first  becomes  apparent  upon  the  opening  of 
the  bolls.  The  most  notable  losses  in  1904,  which  with  little  doubt 
were  due  to  the  conchuela,  were  on  the  farms  of  Mr.  C.  E.  Pierce 
and  Miller  Brothers.  The  former  had  120  acres  of  alfalfa  which 
was  cut  for  the  seed  crop  about  the  middle  of  July,  from  150  to  200 
pounds  of  seed  per  acre  being  expected.  It  was  noticed  that  this 
insect  wTas  very  abundant  in  the  field,  but  the  extent  of  the  damage 
was  fully  realized  only  when  an  average  of  83-J  pounds  of  seed  per 
acre  was  obtained.  At  the  prevailing  value  of  12  cents  per  pound 
the  estimated  loss  was  from  $8  to  $14  per  acre,  or  from  $960  to 
$1,680  for  the  entire  field.  The  10  acres  of  alfalfa  belon£in£  to 
Miller  Brothers  should  have  produced  at  least  150  pounds  of  seed 
per  acre,  according  to  general  estimates,  but  so  much  of  the  seed 
was  ruined,  supposed^  by  the  conchuela,  that  the  yield  was  reduced 
to  60  pounds  per  acre.  The  average  loss  per  acre  was  estimated 
as  at  least  $10.  Other  losses  of  this  kind  occurred  in  Ward  County 
during  1904,  but  the  information  obtainable  concerning  them  is  less 
definite.  According  to  one  report,  alfalfa  growers  at  two  other 
points  in  the  Pecos  River  Valley — Grand  Falls  and  Toyah  Creek — 
experienced  a failure  with  a seed  crop  of  alfalfa  in  that  year  which 
they  attributed  to  “ weevil,'’  a term  commonly  applied  to  the  cause  of 
such  losses  even  before  an  insect  has  been  located  upon  which  to  place 
the  responsibility.  In  this  case  the  writer  believes  that  at  least  the 
greater  part  of  the  losses  in  question  can  be  safely  considered  as  due 
to  the  work  of  Pentatoma  ligata , together  with  the  grain  bug, 
P.  sayi. 

CROPS  DAMAGED  IN  1905. 


ALFALFA. 

Direct  observations,  both  in  western  Texas  and  northern  Mexico, 
showed  that  fields  devoted  to  alfalfa  are  capable  of  harboring  the 
conchuela  in  enormous  numbers.  In  the  Laguna  district  in  Mexico 
alfalfa  has  been  growm  for  several  years,  but  only  for  hay  and  forage, 
and  in  comparatively  small  quantities  on  the  cotton  plantations.  As 
far  as  could  be  learned,  previous  to  1905  the  pest  here  considered 
never  attracted  attention  on  account  of  its  occurrence  in  the  alfalfa 
fields,  but  in  that  year  it  became  so  abundant  that  at  Tlahualilo, 
State  of  Durango,  upon  the  cutting  of  a crop,  adjacent  cotton  fields 
and  a small  vineyard  were  overrun  by  myriads  of  the  insects,  while 
several  miles  distant  at  another  plantation  it  was  first  brought  to  the 
notice  of  the  managers  by  appearing  in  large  numbers  in  the  troughs 
in  which  green  alfalfa  was  fed  to  stock.  In  these  cases,  no  seed 
crop  being  grown,  the  attack  was  limited  to  the  leaves  and  stems. 
The  effect  of  the  extensive  feeding  on  these  parts  can  not  be  definitely 


4 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


stated,  as  in  all  cases  where  plants  without  seed  were  heavily  in- 
fested the  cutting  was  made  before  the  writer  had  an  opportunity  to 
make  an  examination.  According  to  report,  however,  no  marked 
effect  upon  the  plant  was  produced  in  the  instances  here  recorded, 
and,  accordingly,  until  more  is  known,  we  may  assume  that  where 
it  is  not  intended  to  produce  seed  the  principal  danger  incident  to 
the  occurrence  of  the  conchuela  in  alfalfa  fields  lies  in  the  fact 
that  a choice  breeding  place  is  furnished  the  insects,  which  may 
multiply  to  enormous  numbers  and  spread  to  other  crops.  This 
phase  of  the  subject  will  be  discussed  elsewhere  in  this  paper  and  also 
in  a report  on  Heterontera  attacking  the  cotton  plant. 


Fig.  1. — The  conchuela  ( Pentatoma  ligata)  : a,  adult  bug;  b,  egg  mass  on  leaves;  c,  egg 
after  hatching,  lid  removed  showing  egg  burster  ; d,  egg  before  hatching,  from  above ; 
e,  egg  from  side,  showing  lid  above  exit  hole  ; f,  egg  before  hatching,  from  side  ; a,  en- 
larged 4 diam.  ; enlarged  2§  diam. ; c-f,  enlarged  9 diam.  (Author’s  illustration.) 

In  infested  fields  when  the  seed  is  present  the  bugs  may  be  seen 
dinging  to  the  seed  clusters  extracting  the  rich  juices  by  means  of 
their  thread-like  setae.  The  seed  pod,  when  once  fed  upon,  shrivels 
and  turns  dark  and  is  readily  distinguished  from  uninjured  seed 
pods.  Xo  attempt  has  been  made  to  determine  how  rapidly  a bug 
progresses  with  its  destructive  feeding,  but  as  these  insects  are  usualty 
observed  to  be  engaged  in  this  way  as  long  as  desirable  food  remains, 
and  as  the  individual  seed  is  small,  undoubtedly  each  one  of  the 
insects  is  capable  of  destroying  a very  large  number  of  the  seed  pods 
during  its  existence. 

Cutting  of  the  alfalfa  checks  the  multiplication  of  the  pest,  but 
also  has  the  effect  of  driving  the  bugs  elsewhere  in  search  of  food, 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


5 


often  with  more  or  less  serious  results  to  neighboring  crops.  It 
should  also  be  noted  that  the  longer  time  required  to  produce  a seed 
crop  is  favorable  to  the  production  of  large  numbers  of  the  insects. 
Windrows  of  alfalfa  hay,  originally  intended  for  thrashing  for  the 
seed,  in  the  field  of  Mr.  Carson,  at  Barstow,  were  found  to  harbor 
many  adult  conchuelas  which  were  for  the  most  part  busily  engaged 
in  destroying  the  last  few  seed  clusters.  It  would  thus  appear  that 
the  danger  is  not  over  with  the  cutting  of  the  alfalfa,  and  that 
thrashing  should  be  attended  to  as  soon  as  possible  if  the  insects  are 
present  and  injury  is  to  be  avoided. 

The  only  extensive  damage  to  alfalfa  by  this  insect  at  Barstow 
during  1905  was  on  the  farm  of  Mr.  J.  P.  Carson.  Other  growers, 
owing  to  their  experience  of  the  previous  year,  decided  to  grow  no 
seed  crop;  thus  indirectly  many  suffered  a loss  which  should  be 
charged  up  to  the  insect,  as  an  average  crop  of  seed  has  a value  equal 
to  several  times  that  of  a single  cutting  for  hay.  Mr.  Carson  had  55 
acres  ready  for  cutting  for  the  seed  the  last  week  in  July,  but  the 
damage  by  the  bugs  amounted  to  complete  destruction,  for  although 
the  land  was  originally  heavily  seeded,  there  was  not  sufficient  unin- 
jured seed  to  defray  the  expense  of  thrashing.  The  loss  was  consid- 
erably more  than  $1,500,  in  addition  to  the  partial  loss  of  a hay  crop 
in  the  extra  time  allowed  for  the  maturity  of  the  seed. 

Miller  Brothers  in  1905  fortunately  avoided  the  destructive  work 
of  the  insects  and  made  a fair  seed  crop.  At  Barstow  the  interval 
between  cuttings  for  hay  is  on  the  average  about  four  and  one-half 
weeks,  while  for  the  maturity  of  the  seed  an  additional  period  of 
about  three  and  one-half  weeks  is  necessary.  Other  farm  work  pre- 
vented Miller  Brothers  from  cutting  their  alfalfa  when  it  was  in 
prime  condition  for  cutting  for  hay.  As  the  seed  began  to  mature, 
the  scarcity  of  the  pest  which  had  proven  so  destructive  the  previous 
season  caused  the  owners  to  anticipate  a successful  seed  crop.  On  Sep- 
tember 13  the  writer,  who  made  a careful  examination  of  the  condi- 
tion of  the  alfalfa  field  referred  to,  found  the  bugs  scarce,  as  reported, 
and  the  damage  to  the  seed,  which  was  already  mature,  very  slight. 
The  yield  of  seed  reported  by  Miller  Brothers  for  the  10  acres  was 
1,499  pounds. 

MILO  MAIZE. 

On  August  11  a field  of  Milo  maize  Avas  examined  at  Barstowr,  and 
it  was  found  that  in  certain  spots  a considerable  proportion  of  the 
seed  was  ruined,  wdiile  more  or  less  ruined  seed  could  be  found 
throughout  the  field.  According  to  the  owner,  Mr.  Carson,  the  con- 
chuelas had  been  very  abundant  a week  previous,  as  many  as  25  of 
the  insects  frequently  being  noted  on  a single  seed  head.  They  were 
found  to  be  generally  distributed  throughout  the  field  on  August  11, 


6 


MISCELLANEOUS  RESULTS  OE  WORK  OF  BUREAU IX. 


but  in  small  numbers,  the  largest  number  found  on  a single  seed 
head  being  five — two  adults,  two  fourth-instar  nymphs,  and  one  fifth- 
instar  nymph.  On  the  Milo  maize,  as  on  the  alfalfa,  Pentatoma 
ligata  was  accompanied  by  P.  sayi , but  in  more  nearly  equal  numbers ; 
this  is  not  necessarily  of  any  special  significance,  though  possibly  it 
may  indicate  a preference  of  the  latter  species  for  the  seed  of  the 
grains. 

COTTON. 

The  first  examination  for  the  conchuela  in  the  cotton  fields  at 
Barstow  was  on  August  11,  when  of  the  five  fields  visited  specimens 
of  the  insect  were  found  in  all  except  one.  In  every  case  the  number 
of  damaged  bolls,  although  in  small  proportion,  gave  evidence  of  the 
occurrence  of  the  insect  in  somewhat  larger  numbers  some  weeks 
previous.  In  one  field  an  examination  of  100  plants  showed  an  in- 
festation of  5 per  cent  of  the  plants,  with  12  adults  per  100  plants. 
The  damage  to  the  bolls  in  this  field  amounted  approximately  to  15 
per  cent.  Another  field  of  about  10  acres  was  found  to  be  damaged 
to  a less  extent  except  for  about  one-half  an  acre  near  one  side  where, 
of  60  bolls  selected  at  random,  30  per  cent  were  destroyed  by  bugs. 
The  writer  estimates,  as  a result  of  personal  examinations  in  many 
fields  at  and  near  Barstow,  that  the  average  damage  to  cotton  by  the 
conchuela  in  1905  was  about  10  per  cent. 

PEACHES. 

Although  peaches  have  been  grown  at  Barstow  for  several  years 
we  have  no  report  of  damage  to  the  fruit  by  the  conchuela  or  other 
bugs  until  1905,  when  the  matter  was  reported  by  Mr.  C.  E.  Pierce 
and  investigated,  as  stated  in  the  introduction,  by  Mr.  Crawford  and 
the  writer.  The  attack  was  confined  to  the  fruit  of  the  earliest  varieties 
in  their  first  fruiting  season.  The  trees  were  located  on  the  side  of 
the  orchard  adjacent  to  the  120-acre  alfalfa  field,  the  damage  to  the 
seed  crop  of  which  in  the  previous  year  has  already  been  mentioned. 
Shortly  after  the  10th  of  July,  coincident  with  the  cutting  of  the 
alfalfa,  the  bugs  were  noticed  on  the  fruit  of  these  trees,  which  was 
just  beginning  to  ripen.  The  trees  soon  became  very  heavily  infested, 
and  on  July  20  it  was  not  uncommon  to  observe  from  10  to  15  on  a 
single  peach  and  in  one  instance  20  were  counted.  The  tendency 
of  the  conclnielas  to  congregate  on  certain  individual  peaches  was 
very  marked,  as  has  likewise  been  observed  in  their  occurrence 
upon  cotton  bolls.®  On  the  most  heavily  infested  trees,  owing  to 
this  habit,  many  peaches  at  any  given  time  seemed  neglected,  but 
all  on  the  attacked  trees  were  ultimately  destroj^ed.  The  injured 
fruit  became  shrunken  in  spots  and  sponge-like  to  the  touch,  finally 

o Bui.  54,  Bur.  Ent.,  U.  S.  Dept.  Agric.,  p.  26,  1905. 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


7 


falling  to  the  ground.  It  was  apprehended  that  the  pests  would 
transfer  their  attention  to  the  late  peaches  when  these  began  to 
ripen,  and  a few  were  observed  to  do  so,  but  apparently  when  the 
supply  of  early  peaches  was  exhausted  or  rendered  unfit  for  further 
feeding,  the  late  peaches  wTere  not  mature  enough  to  be  attractive, 
and  consequently  suffered  practically  no  injury  from  this  source. 

GRAPES. 


In  1905  at  Barstow  the  fruit  in  the  vineyards  was  in  general 
only  slightly  affected  by  Pentatoma  ligata.  The  principal  damage 
was  in  the  small  gardens  in  town,  where  in  certain  instances  the 
destruction  wTas  practically  complete.  Probably  owing  to  the  large 
area  occupied  by  the  vineyards  and  to  the  fact  that  the  fruit  of  the 
different  varieties  ripens  at  about  the  same  time,  no  especial  con- 
centration of  the  insects  in  the  large  vineyards  was  noticed,  and  there 
was  no  indication  that  any  such  concentration  occurred.  The  ripe 
fruit  is  preferred,  although  when  the  food  supply  is  short  it  may  be 
attacked  when  immature.  The  injured  berry  shrivels  and  under  the 
influence  of  the  hot  sun  soon  becomes  raisin-like. 

At  Tlahualilo,  Durango,  Mexico,  on  July  17,  1905,  a vineyard  of 
about  10  acres  with  vines  heavily  loaded  with  fruit  became  thor- 
oughly infested  by  direct  migration  from  an  adjacent  alfalfa  field 
of  adults  and  of  nymphs  in  the  last  two  instars.  Each  cluster  of 
grapes  was  attacked  by  several  bugs,  the  maximum  noted  on  a single 
cluster  being  25.  Without  consultation  with  the  writer  the  grapes 
wTere  picked  immediately  upon  discovery  of  the  infestation,  the  pre- 
sumption being  that  the  removal  of  their  food  would  serve  as  a 
check  to  the  insects,  to  the  benefit  of  the  cotton  fields.  This  step 
was,  however,  inadvisable,  since  the  fruit,  which  was  of  compara- 
tively small  value,  would  have  served  as  a trap  at  which  the  bugs 
could  have  been  easily  destroyed  when  so  thickly  congregated.  As 
it  was,  the  bugs  gathered  in  groups  of  hundreds  on  the  trellis  posts 
and. on  the  vines,  principally  at  the  forks,  where  they  were  destroyed, 
partly  by  spraying  and  partly  by  use  of  a gasoline-blast  torch.  The 
last-mentioned  method,  while  effective  in  its  destruction  of  the  pest, 
injured  the  vines  to  a certain  extent  in  nearly  all  cases. 

GARDEN  VEGETABLES. 

Between  the  middle  of  July  and  the  middle  of  August  garden 
crops  at  Barstow  were  affected  to  a considerable  extent  by  this 
destructive  pest.  Owing  to  the  comparatively  small  amount  of  land 
devoted  to  such  crops,  the  actual  money  equivalent  of  the  loss  was 
not  great.  The  crops  which  suffered  most  were  peas,  beans,  and 
tomatoes.  In  each  case  the  attack  was  restricted  almost  entirely  to 


8 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


the  seed  or  fruit,  thus  accomplishing  a maximum  of  damage.  Under 
another  heading  the  writer  has  referred  to  the  destruction  of  peas 
and  beans  in  Western  Texas,  not  far  from  Barstow,  by  the  grain 
bug.  Among  other  cases  on  record  which  give  further  evidence  of 
the  losses  pentatomid  bugs  may  cause  by  their  attacks  on  vegetables 
is  one  quoted  by  H.  G.  Hubbard a from  the  report  of  a Florida 
correspondent  on  his  experience  with  a species  commonly  called  the 
green  tree  bug  ( Nezara  hilaris  Say).  According  to  the  report,  this 
species  attacked  cowpea  vines  before  any  seed  was  developed  and 
completely  ruined  35  acres  of  this  crop,  so  that  no  good  seed  was 
obtained.  A garden  crop  of  tomatoes  was  also  reported  to  have  been 
entirely  destroyed,  the  ground  under  the  vines  being  almost  covered 
by  the  fallen  fruit.  The  injured  fruit  was  described  as  reddish- 
yellow  in  color  at  the  point  punctured,  and  when  cut  was  found  to 
be  “ full  of  lumps  and  totally  devoid  of  flavor.”  These  records  of 
the  damage  by  other  pentatomid  bugs  to  general  garden  crops  show 
the  extent  to  which  the  conch uela  is  capable  of  affecting  these  crops 
when  they  are  grown  on  a more  extensive  scale  than  was  the  case  at 
Barstow  at  the  time  the  observations  recorded  in  this-  paper  were 
made. 

OTHER  FOOD  PLANTS. 

The  principal  natural  food  plants  of  the  conchuela  are  the  mesquite 
and  related  leguminous  plants,  the  beans  being  the  ojrject  of  attack. 
It  would  require  more  than  one  season’s  observations  to  determine 
how  important  is  the  connection  between  the  abundance  of  mesquite 
beans  and  the  abundance  of  the  insects  on  cultivated  plants.  It  is 
presumable  that  during  the  period  when  the  insects  are  multiplying 
most  rapidly  the  abundance  of  rich  food  such  as  the  mesquite  bean 
provides  is  an  important  factor  in  determining  the  amount  of  subse- 
quent injury  to  crops.  At  Barstow,  in  addition  to  the  mesquite  and 
the  crops  which  have  been  separately  discussed,  the  conchuela  has 
been  found  feeding  on  the  fruit  of  peppers,  on  squash  vines,  and  on 
the  leaves  of  yucca.  It  has  also  been  reported  on  good  authority  to 
have  been  observed  in  considerable  numbers  on  corn,  and  the  writer 
has  in  Mexico  found  egg  batches  of  this  species  attached  to  the  green 
leaves  of  corn.  In  general,  the  species  may  be  said  to  be  almost 
omnivorous,  showing  a preference,  however,  for  fruits  and  seeds. 

SEASONAL  HISTORY. 

The  multiplication  of  the  conchuela  in  western  Texas  seems  to  fol- 
low the  same  course  as  has  been  observed  in  northern  Mexico;  in 
other  words,  the  maximum  number  is  reached  between  the  middle  and 

a Report  on  Insects  Affecting  the  Orange.  Div.  Ent.,  U.  S.  Dept.  Agric.,  p. 
1G0,  1885. 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


9 


last  of  July,  after  which  the  number  diminishes  rapidly.  The  bugs 
are  strong  fliers,  which  accounts  for  their  sudden  appearance  on  a 
given  crop,  and  in  some  cases  for  their  sudden  clisappearence  from  it. 

On  July  20-22  no  eggs  or  young  could  be  found  on  the  infested 
peach  trees,  nor  could  any  of  these  stages  be  found  on  August  11  and 
12  after  the  adults  had  entirely  disappeared  from  the  trees.  If  any 
eggs  were  deposited  by  the  bugs  when  the  latter  were  attacking  the 
peaches  the  resulting  nymphs  were  probably  carried  to  the  ground 
with  the  falling  of  the  fruit,  for  the  interval  between  the  examina- 
tions was  not  sufficiently  long  for  them  to  have  reached  the  winged 
or  adult  stage.  The  only  breeding  places  of  consequence  found  at 
Barstow  were  in  the  alfalfa  fields.  Here  eggs  and  nymphs  were  found 
in  large  numbers  on  August  11  and  12.  A month  later  the  insects 
had  been  reduced  by  at  least  one-half,  and  their  scarcity  was  noticeable 
everywhere  except  in  small  areas  in  some  fields  of  alfalfa  and  along 
the  borders  near  fences  and  ditches  where  the  cuttings  had  not  been 
made  at  regular  intervals.  Of  32  adult  pentatomids  collected  in  the 
alfalfa  fields  September  12,  26  were  P.  ligata  and  6 P.  sayi.  At  the 
next  examination,  on  October  13,  it  was  evident  that  the  insects  were 
still  decreasing  in  numbers,  but  the  nymphs  in  the  last  two  stages 
were  proportionally  more  abundant  than  before.  In  the  lot  of  16 
adults  and  49  nymphs  collected  at  that  time,  P.  sayi  was  not  repre- 
sented. The  last  examination,  made  on  November  14,  showed  that 
the  conchuelas  had  almost  entirely  disappeared ; a half  hour’s  search 
where,  at  the  time  of  previous  examinations,  they  had  been  found 
most  abundant,  resulted  in  the  capture  of  only  6 adults,  no  nymphs 
being  seen. 

NATURAL  ENEMIES. 

EGG  PARASITES. 

Minute  egg  parasites  belonging  to  the  family  Proctotrypidae  are 
generally  known  among  entomologists  to  play  an  important  role  in 
checking  the  multiplication  of  many  insects,  so  that  anything  which 
affects  the  numbers  of  these  parasites  frequently  results  in  a corre- 
sponding benefit  or  injury  to  the  crops  attacked  by  the  host  insects. 
If  these  parasites  of  the  eggs  of  pentatomids  were  eliminated,  many 
of  the  pentatomids  would  undoubtedly  be  ranked  among  our  most 
important  insect  pests.  The  importance  of  these  parasites  in  check- 
ing the  multiplication  of  the  conchuela  at  Barstow  in  19.05  can  be 
best  emphasized  by  summarizing  the  results  obtained  by  rearing 
parasites  from  eggs  collected  at  that  place. 


10  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Hummary  of  results  obtained  by  rearing  parasites  from  eggs  of  Pentatoma 
ligata  collected  at  Barstow,  Tex.,  in  1905. 


When  collected. 

Number 
of  egg 
batches. 

Total 
number 
of  eggs. 

Number  1 
of  eggs 
hatched. 

Per  cent 
hatched. 

1 Number 
of  para- 
sites 

emerged. 

Per  cent 
produc- 
ing para- 
sites. 

Number 
of  eggs 
destroyed 
by  other 
agencies. 

Per  cent 
failing  to 
produce 
nymphs. 

August  11-12 

6 

181 

35 

19 

41 

22 

0 

81 

September  12 

13 

246 

20  I 

8 

148 

54 

a 35 

92 

Total 

19. 

427 

55 

13 

189 

44 

35 

87 

a Representing  two  batches  of  13  and  22  eggs,  respectively.  Presumably  destroyed  by  ants,  the 
broken  eggshells  remaining. 


Shrinking  of  the  eggs,  indicating  infertility,  occurred  in  no  case 
among  the  eggs  included  above.  From  the  fact  that  adult  para- 
sites frequently  fail  to  emerge  from  the  egg  of  the  host  even  after 


Fig.  2. — Telenomus  ashmeadi,  an  important  egg  parasite  of  Pentatoma  ligata:  Adult  female  and  antenna  I 
of  male.  Highly  magnified  (original). 

breaking  through  the  shell — and  as  far  as  observed  it  seldom  occurs  J 
in  nature  that  eggs  of  the  conchuela  fail  to  hatch  when  not  destroyed  | 
by  outside  agencies — it  may  be  concluded  that  practically  all  the  I 
eggs  appearing  intact  which  failed  to  hatch  were  destroyed  by  the  1 
parasites.  In  support  of  this  supposition  IQ  eggs  which  neither  1 
hatched  nor  from  which  live  parasites  emerged,  selected  at  random  I 
from  the  19  batches  above  mentioned,  were  opened  and  each  was  I 
found  to  contain  a dead  adult  parasite.  The  specimens  bred  from  I 
the  eggs  of  P.  ligata  and  also  of  P.  sayi  from  Barstow  were  all  of  the  1 
same  species  and  identified  by  Dr.  William  H.  Ashmead,  of  the  U.  S.  1 
National  Museum,  as  a new  species  of  the  genus  Telenomus  (fig.  2).  I 
The  •writer  will  describe  the  species  under  the  name  Telenomutt  I 
aslimeadi.  An  egg  batch  of  the  conchuela  containing  hatched  and  | 
unhatched  eggs  is  shown  in  Plate  I,  figure  1,  and  a parasitized  egg  I 
batch  in  Plate  I,  figure  2.  . 


Bui.  64,  Part  I,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture  PLATE  I. 


Fig.  1 Egg  Batch  of  Conchuela  (Pentatoma  ligata),  Showing  Hatched  and 
Unhatched  Eggs.  Enlarged  6!  Diameters  (Original). 


Fig.  2.— Egg  Batch  of  Conchuela  (Pentatoma  ligata)  from  which  32 
Proctotrypid  Parasites  (Telenomus  ashmeadi)  have  Emerged.  Enlarged 
61  Diameters  (Original). 

The  illustration  shows  three  parasites,  including  male  and  female,  ready  to  emerge;  also 
an  egg  destroyed,  probably  by  an  ant. 


library 

UNIVERSITY  Of  ILLINOIS 
URBANA 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


11 


TACHINID  PARASITES. 

A species  of  the  very  useful  family  Tachinidse,  Gymnosoma  fuli- 
ginosa  Desv.,  has  been  reared  from  adults  of  the  conchuela.  The 
victims  of  this  parasitic  fly  are  distinguished  by  the  yellowish-white 
egg  or  eggshell  which  remains  attached  to  the  thorax  of  the  host 
unless  it  happened  to  have  been  attached  to  a nymph  in  the  fifth 
instar,  which  afterwards  molted.  On  August  11  and  12  only  three 
parasitized  specimens  were  discovered,  two  in  the  fifth  nymphal 
instar  and  one  an  adult.  An  adult  of  this  species  of  Tachinidae  was 
bred  from  one  of  these  bugs.  On  September  12  parasitism  by  these 
tachinids  was  found  to  be  more  common  than  at  the  time  of  the 
previous  visit.  Of  24  adults  examined  at  that  time,  4 were  found 
to  be  parasitized.  On  October  13,  of  18  adults  and  31  nymphs  in 
the  fifth  nymphal  instar,  2 only  had  been  parasitized,  both  nymphs. 
While  these  parasites  are  decidedly  beneficial  and  may  be  more  useful 
under  some  conditions,  they  were  not  sufficiently  abundant  at  Barstow 
in  1905  to  explain  the  rapid  decimation  of  the  numbers  of  the  con- 
chuela which  has  been  described  under  the  subject  of  seasonal  history. 

PREDACEOUS  - ENEMIES. 

Although  no  observations  on  tlie  subject  of  predaceous  enemies 
were  made  at  Barstow,  it  seems  important  to  refer  briefly  to  the 
records  of  observations  by  others  along  this  line,  in  order  that  it  be 
not  inferred  that  because  pentatomids  in  general  are  characterized 
by  their  ability  to  produce  an  offensive  odor  they  are  immune  to  the 
attacks  of  insectivorous  birds  and  of  toads.  On  the  contrary  the 
crow®  is  believed  to  be  especially  fond  of  bugs  of  this  group,  and 
many  other  birds,*  & as  well  as  the  common  toads,®  seem  to  find  them 
unobjectionable  as  food.  If  we  accept  the  evidence  of  definite  reports 
and  observations  during  three  successive  seasons  as  indicative  of  the 
usual  seasonal  history  of  the  conchuela,  the  period  of  maximum  abun- 
dance is  followed  closely  by  a marked  reduction  in  the  numbers  of 
the  pest.  In  this  it  is  not  unlikely  that  birds  will  prove  to  be  an 
important  if  not  the  leading  factor. 

METHODS  OF  CONTROL. 

Under  some  conditions  farm  practices,  such  as  the  destruction  of 
weeds  in  the  fall  and  otherwise  hindering  the  sucessful  hibernation  of 
the  conchuelas,  would  be  of  unquestioned  value  in  control,  but  under 

a Bui.  6,  Div.  Orn.  and  Mam.,  U.  S.  Dept.  Agric.,  p.  63. 

& Buis.  13,  Biol.  Surv.,  Dept.  Agric.,  U.  *S.,  pp.  25,  62.  70 ; 15,  p.  23 ; 21,  p.  43 ; 
23,  p.  26.  Yearbook  U.  S.  Dept.  Agric.  for  1895,  pp.  417,  423,  429;  Yearbook 
U.  S.  Dept.  Agric.  for  1900,  p.  414,  Plates  L,  LI. 

c Bui.  46,  Hatch  (Mass.)  Exp.  Sta.,  p.  26.  Bui.  91,  Ky.  Exp.  Sta.,  pp.  62,  64. 


12 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


the  conditions  in  western  Texas,  such  as  those  obtaining  at  Barstow, 
probably  little  good  could  be  accomplished  by  such  measures.  With 
the  mesquite-covered  surrounding  districts  as  a stronghold  these 
insects  probably  will  become  established  in  the  alfalfa  fields  each  year 
and  become  more  or  less  numerous  as  the  season  progresses,  their 
numbers  being  governed  by  conditions  which  for  the  most  part  exert 
their  influence  secondarily  through  the  natural  enemies  of  the  species. 
The  question  of  control  at  Barstow,  and  where  similar  conditions 
prevail,  resolves  itself  into:  First,  avoidance  of  damage  to  the  seed 
crop  of  alfalfa ; second,  methods  tending  to  prevent  the  insect’s 
spread  from  alfalfa  to  other  crops,  or  otherwise  preventing  infesta- 
tions : third,  direct  remedies  applicable  for  use  when  crops  other  than 
alfalfa  become  infested. 

AVOIDANCE  OF  INJURY  TO  THE  SEED  CROP  OF  ALFALFA. 

At  Barstow  the  experience  of  alfalfa  growers  for  two  successive 
seasons,  supported  by  direct  observation  by  Mr.  Crawford  and  the 
writer  at  regular  intervals  during  1905,  has  shown  that  the  conchue- 
las  are  so  numerous  during  July  and  August  that  an  attempt  to  pro- 
duce a seed  crop  during  this  period  would  be  inadvisable.  In  north- 
ern Mexico  observations  extending  over  three  seasons  have  shown  the 
insects  both  to  reach  a maximum  in  numbers  and  to  show  a marked 
decrease  therefrom  during  the  last  two  weeks  of  July.  This  cor- 
responded with  the  history  of  the  pest  at  Barstow,  and  it  is  believed 
that  the  danger  limits  above  given  are  sufficiently  wide  to  cover*  all 
but  exceptional  cases  under  the  present  conditions.  If  a crop 
intended  for  seed  promised  to  mature  before  July  1,  probably  but 
little  damage  would  be  accomplished  by  the  concliuela,  but  this  is 
entirely  a surmise  which  it  is  hoped  will  be  thoroughly  tested  when 
an  opportunity  presents  itself.  The  same  probabilities  hold  for  a crop 
of  seed  which  would  mature  after  the  1st  of  September.  This,  more- 
over, has  been  substantiated  by  the  experience  of  Miller  Brothers  at 
Barstoiv,  which  has  been  described  under  the  subject  of  damage  to 
alfalfa  in  1905.  Avoidance  of  the  injury  as  here  outlined  is  undoubt- 
edly simpler  than  actually  defending  the  seed  in  the  field  from  attack. 

A SUGGESTION  AS  TO  MECHANICAL  CONTRIVANCES  FOR  COLLECTING  THE 

INSECTS. 

Between  the  concliuela  ( P . ligata ) and  its  near  relative,  the  grain 
bug  (P.  sayi) , whose  reputation  as  a pest  has  already  been  men- 
tioned, it  may  be  anticipated  here  that  in  the  course  of  time  remedies 
will  be  demanded  for  use  against  such  insect  enemies  of  alfalfa  in 
other  sections  of  the  country.  In  a field  with  ripening  seed  an  ex- 
periment with  an  insect-collecting  net  in  one  hand  and  a stick  in  the 
other,  simulating  the  action  of  an  imaginary  specially  constructed 


MEXICAN  CONCHUELA  IN  WESTERN  TEXAS  IN  1905. 


13 


bopperdozer  with  a revolving  fan,  convinced  the  writer  of  the  prac- 
ticability of  collecting  these  insects  mechanically.  The  great  major- 
ity of  the  insects,  when  undisturbed,  may  be  found  near  the  tops  of 
the  plants,  on  the  seed  clusters  when  these  are  present.  They  drop 
to  the  ground  when  slightly  disturbed,  much  more  readily,  in  fact, 
than  when  they  have  a footing  on  a more  substantial  object  like  a 
cotton  boll.  It  is  safe  to  predict  that  a contrivance  for  collecting  will 
be  devised  when  the  necessity  arises.  It  should  be  light,  operated 
from  behind,  and  consist  essentially  of  an  elongate  metallic  pan  sus- 
pended below  a revolving  fan  geared  to  the  supporting  wheels. 

PREVENTIVE  AND  PROTECTIVE  MEASURES. 

If,  as  advised  in  one  of  the  preceding  paragraphs,  no  attempt  is, 
made  to  produce  a seed  crop  during  the  period  of  the  year  when  the 
conchuelas  are  dangerously  abundant,  an  important  factor  in  their 
multiplication  and  spread  will  be  eliminated.  But  the  shorter  period 
required  for  the  hay  crop  is  sufficient  to  permit  the  insects  to  reach 
the  enormous  numbers  indicated  in  the  writer’s  reference  to  the  occur- 
rence on  alfalfa  in  northern  Mexico  in  1905.  Uusually  the  greater 
number  of  the  insects  will  not  reach  maturity  during  the  interim  be- 
tween cuttings,  and  the  work  of  preventing  the  spread  will  be  in  part 
the  checking  of  the  migration  of  the  crawling  nymphs.  This  can  be 
readily  accomplished  when  necessary  by  leaving  an  uncut  border 
around  the  field,  where  the  insects  when  trapped  can  be  destroyed  by 
spraying  with  kerosene  emulsion.  As  the  insects  show  a marked 
tendency  to  concentrate  in  certain  limited  areas  rather  than  to  spread 
evenly  over  the  fields,  this  can  be  taken  advantage  of  by  making  a 
general  examination  of  the  field,  before  cutting,  to  locate  the  colonies. 
A few  small  boys  in  a few  hours  might  pick  up  several  quarts  ° of  the 
adults  when  these  are  abundant  and  well  concentrated.  If  this  is  not 
feasible,  small  heavily  infested  areas  may  be  treated  with  kerosene 
emulsion,  although  adult  pentatomids  are  apt  to  be  quite  resistant 
to  this  insecticide.  At  Tlahualilo,  Durango,  Mexico,  on  July  11, 
1905,  after  the  alfalfa  hay  had  been  made  and  stacked,  countless 
hosts  of  the  insects  still  remained  in  the  alfalfa  field  in  spite  of  the 
extensive  migration  to  neighboring  crops.  Those  that  remained 
were  largely  concentrated  near  one  corner  of  the  field  and,  as  suitable 
spraying  apparatus  was  not  available,  destruction  of  the  pest  was 
accomplished  by  respreading  about  3 or  4 tons  of  alfalfa  hay  over 
the  ground  and  then  burning  it.  This  operation  for  the  protection 
of  the  surrounding  cotton  fields  against  further  invasion  from  this 
source  was  effective,  but  would  be  unnecessarily  costly  under  ordinary 


« One  quart  contains  approximately  1,500  adult  specimens  of  P.  ligata. 


14  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


circumstances.  In  the  case  of  the  chinch  bug  a practice  of  destruc- 
tion by  burning  similar  to  the  one  here  mentioned  has  been  recom- 
mended for  use  under  certain  conditions.0  Cooperation  among  the 
owners  of  adjoining  farms  is  necessary  in  order  to  obtain  the  best 
results  in  the  attempt  to  check  the  spread  of  the  conchuela,  as  well 
as  in  the  case  of  the  chinch  bug  and  many  other  insects. 

A protective  measure  which  may  in  some  cases  be  recommended, 
especially  for  use  in  small  gardens,  consists  in  screening  such  crops  as 
tomatoes  with  a cheap  quality  of  mosquito  netting. 

REMEDIES  WHEN  CROPS  OTHER  THAN  ALFALFA  ARE  ATTACKED. 

The  subject  of  remedies  for  use  in  protecting  cotton  against  damage 
by  the  conchuela  and  related  pests  will  be  reserved  for  a future  pub- 
lication. When  this  insect  attacks  the  seed  of  Milo  maize  and  related 
grains  little  can  be  done  except  when  the  bugs  are  concentrated  in 
large  numbers  in  limited  areas;  then  hand  collecting  or  jarring  from 
the  plants  may  be  advisable,  particularly  as  a protective  measure 
when  such  an  infestation  is  an  element  of  danger  to  neighboring 
crops.  For  remedial  measures  against  the  insect  when  it  attacks 
garden  vegetables  and  grapes  we  can  suggest  spraying  with  kerosene 
emulsion  and  collecting  by  hand,  or,  if  it  is  necessary  to  carry  on 
operations  on  a large  scale,  the  bugs  may  be  jarred  into  convenient 
receptacles  containing  kerosene  and  water,  so  arranged  that  they  can 
be  dragged  between  the  rows  if  desired. 

When  attacking  peaches  a certain  proportion  of  the  bugs  can  be 
jarred  from  the  fruit  and  killed  on  the  ground,  but  this  is  at  the 
best  far  from  satisfactory,  as  the  fruit  itself  is  likely  to  be  shaken  off 
or  otherwise  injured  and  many  of  the  bugs  will  escape  by  flying. 
Peach  trees  when  pruned  in  accordance  with  the  practice  of  the  lead- 
ing growers  are  low  enough  to  permit  hand  picking  of  all  the  fruit 
and  are  correspond ingW  easy  of  fumigation.  A light  tent  made  of 
ordinary  cotton  sheeting  can  be  placed  over  an  infested  tree  by  the  use 
of  poles  and  held  in  place  at  the  bottom  by  dirt  or  stones.  The  burn- 
ing of  tobacco  stems,  pyrethrum,  or  buhach  powder  inside  the  tent 
will  soon  stupefy  the  insects  and  cause  them  to  fall  to  the  ground, 
where  they  can  be  easily  and  quickly  killed.  The  fumes  can  be  pre- 
vented from  escaping  too  readily  through  the  cloth  hy  lightly  paint- 
ing it  with  linseed  oil  thinned  with  turpentine.  This  method  of  fumi- 
gation is  inexpensive  and  has  the  further  advantage  of  requiring  but 
a few  minutes’  work  for  each  tree. 

« Bui.  17,  old  series,  Div.  Ent.,  U.  S.  Dept.  Agric.,  p.  37,  1888. 


O 


U.  S.  DEPARTMENT  OE  AGRICULTURE, 
BUREAU  OF  ENTOMOLOGY  BULLETIN  No.  64,  Part  II. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OE  ENTOMOLOGY— IX. 


NOTES  ON  THE 

ECONOMIC  IMPORTANCE  OF  SOWBUGS. 


W.  DWIGHT  PIERCE, 

Special  Field  Agent. 


Issued  April  2,  1907. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1907. 


. 


9 


CONTENTS. 


Page. 

Armadillidium  vulgare  Latr 15 

Remedies 21 

Porcellio  Icevis  Latr 21 

Metoponorthus  pruinosus  Brandt 22 

Conclusions 22 


ILLUSTRATION. 


Page. 

Plate  II.  Work  of  Armadillidium  vulgare  on  cotton 1G 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  II. 


Issued  April  2,  1907. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK  0E 
THE  BUREAU  OF  ENTOMOLOGY— IX. 

NOTES  ON  THE  ECONOMIC  IMPORTANCE  OF  SOWBUGS. 

By  W.  Dwight  Pierce, 

Special  Field  Agent. 

9 

Haying  been  detailed  to  investigate  certain  injuries  attributed  to 
sowbugs,  the  writer  presents  the  following  notes  concerning  the  life 
history  and  habits  of  three  species  of  these  isopods,  namely,  Armadil- 
lidiwn  vulgare  Latr.,  P orcellio  Icevis  Latr.,  and  M etoponorthus  prui- 
nosus  Brandt.  The  first  species,  at  least,  is  capable  of  doing  con- 
siderable injury  to  garden  crops,  flower  gardens,  vines,  and  field 
crops  in  the  vicinity  of  buildings,  although  it  is  also  found  to  be  a 
valuable  scavenger.  The  scavenger  habit,  however,  makes  it  an  unde- 
sirable intruder  in  the  house  owing  to  the  possibility  that  it  may 
convey  disease. 

ARMADILLIDIUM  VULGARE  Latr. 

The  sow  bug  Armadillidium  vulgare  Latr.  is  commonly  known  as 
the  “ pill-bug,”  on  account  of  its  habit  of  rolling  into  a ball  whenever 
disturbed.  Ordinarily  it  is  found  only  in  the  vicinity  of  habitations, 
in  dark,  damp  places,  such  as  woodsheds  and  cellars,  under  boards 
and  rubbish,  and  around  wells,  cisterns,  and  water  barrels.  The  open 
foundations  under  houses  in  the  South  give  very  favorable  locations 
for  breeding. 

For  several  years  the  Department  of  Agriculture  has  received 
reports  of  injury  from  sowbugs  to  one  or  another  crop  in  various 
parts  of  Texas.  The  sowbugs  seem  to  have  been  on  the  increase  from 
year  to  year.  In  1905  the  spring  rains,  although  at  times  occasioning 
a natural  check  to  these  pests,  brought  about  a series  of  conditions 
favorable  to  a rapid  increase  in  their  numbers.  Moisture  is  a requisite 
to  their  life,  and  it  also  seenis  that  vegetation  is  a standard  article  of 
food.  The  bad  conditions  of  the  ground  throughout  Texas  during 
that  year  made  all  crops  very  late,  so  that  by  the  time  the  succulent 
cotton  and  garden  crops  were  coming  up  the  new  broods  of  young 
sowbugs  were  everywhere  engaged  in  finding  delicate,  tender  food. 

15 


16  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


At  Dallas  the  cotton  patch  of  the  boll-weevil  laboratory  furnished 
ample  evidence  of  the  capacity  of  these  crustaceans  in  devouring 
vegetation  (see  Pl.  II).  By  April  14  the  cotton  was  sending  up  the 
second,  and  in  some  cases  the  third,  pair  of  leaves.  At  this  time  Mr. 
Springer  Goes  noticed  that  the  growing  tips  in  rows  adjacent  to 
buildings  were  badly  eaten,  although  the  injury  extended  over  the 
entire  patch  to  a greater  or  less  degree.  All  plants  Avhich  were  tipped 
died  very  shortly,  with  the  result  that  seven  rows  had  to  be  entirely 
replanted.  A great  many  of  the  seedlings  of  the  second  planting  also 
were  killed.  Many  gardens  had  suffered  through  attacks  on  the  young 
sprouts  of  beans,  peas,  and  tomatoes,  and  on  rose  bushes  and  other 
cultivated  flowers.  In  December  Mr.  R.  C.  Howell  found  the  sow- 
bugs  doing  serious  damage  to  roots  of  palmetto,  one  large  plant  being 
entirely  killed.  From  Austin  there  came  a note  published  in  Farm 
and  Ranch,  dated  April  29,  1905,  which  enumerated  the  following 
plants  as  subject  to  the  attacks  of  this  species:  Butter  beans,  radishes, 
lettuce,  mustard,  potted  plants,  and  also  flower  seed.  The  earlier 
planting  of  beans  was  untouched,  while  the  late  planting,  owing  to 
the  favorable  conditions  for  multiplication  afforded  the  sowbugs,  was 
seriously  injured. 

From  economic  literature  the  writer  finds  the  following  records  of 
injury  attributed  to  this  species: 

Miss  Richardson®  cites  injuries  to  cucumbers  and  hothouse  vege- 
tables at  New  Orleans,  La.,  to  various  plants  at  Fort  Worth,  Tex., 
and  to  date  palms  from  Algeria,  located  at  Washington,  and  states 
that  these  sowbugs  are  a most  serious  pest  on  mushrooms  at  Berkley, 
Va. 

Mr.  H.  Garman 6 cites  this  species  as  very  injurious  to  young 
cucumbers  and  lettuce  in  greenhouses,  and  recommends  carbon  bisul- 
phid  as  a remedy. 

With  this  information  in  hand,  a series  of  seventy-five  experiments 
was  conducted  in  the  laboratory  in  order  to  compare  various  condi- 
tions and  foods  in  their  effects  upon  this  species.  Over  900  individuals  j 
were  involved  in  the  experiments,  of  which  the  results  may  be  here  j 
summarized. 

The  most  favorable  condition  under  which  to  keep  the  sowbugs  was 
found  to  consist  of  a mixture  of  gumbo  and  sand  kept  moist,  and  a 
supply  of  fresh  cotton  leaves,  leaving  some  old  ones  to  decay  and  I 
mold.  Moisture  is  absolutely  essential.  With  such  conditions,  sow-1 
bugs  were  carried  through  the  entire  period  of  the  investigation,  e.  g., 
10  females  and  1 male  were  kept  alive  eighty  days,  and  4 of  these  j 

a Monograph  on  the  Isopods  of  North  America.  By  Harriet  Richardson.! 
Bui.  54,  U.  S.  Nat.  Mus.,  1905.  I 

& Bui.  91,  Ky.  Agric.  Exp.  Sta.,  1901.  I 


Work  of  Armadillidium  vulgare  on  Cotton. 


Bui.  64,  Part  II,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture. 


Plate  II. 


library 

UNIVERSITY  OF  ILLINOIS 
URBANA 


ECONOMIC  IMPORTANCE  OF  SOWBUGS. 


17 


females  were  still  alive  one  hundred  and  sixty  days  after  the  begin- 
ning of  the  experiment.  The  cotton  leaves,  when  tender,  were  eagerly 
eaten. 

Fungous  growth  was  favorable  only  under  certain  conditions.  In 
the  experiments  cited  above  the  leaves  in  contact  with  the  earth  de- 
cayed and  accumulated  a rich  growth  of  mold.  Upon  these  decayed 
leaves  the  sowbugs  seemed  to  thrive,  although  there  was  always  evi- 
dence of  feeding  on  green  leaves  when  such  were  present.  Fungous 
growths  on  dry  leaves,  on  decaying  fruit,  and  on  moist  dead  wood 
were  only  capable  of  sustaining  them  as  long  as  the  moisture  was  con- 
served. Fungus  found  on  earth  moistened  with  molasses  sustained 
9 sowbugs  thirty-six  days,  and  2 survived  as  long  as  seventy-five  days. 
Green  cotton  leaves  alone  will  sustain  the  life  of  these  crustaceans 
longer  than  any  other  simple  condition  tried — thirty-two  days  being 
the  longest  any  remained  alive  under  these  conditions.  The  other 
vegetation  provided  was  not  favorable,  and  the  sowbugs  seemed 
rather  to  keep  alive  on  the  moisture  from  the  blotter  or  on  the  fungus- 
covered  decayed  leaves;  thus,  rose  buds  and  leaves,  and  the  leaves  of 
violet,  mint,  and  chrysanthemum  were  untouched  by  the  sowbugs. 
These  leaves  did  not  retain  their  moisture  long  after  picking.  When 
moist  earth  alone  was  provided,  some  found  sufficient  food  to  sustain 
life  eighteen  days.  Additional  proof  that  nourishment  is  sought  in 
the  soil  was  obtained  by  mixing  London  purple  or  Paris  green  with 
the  earth.  Death  always  resulted  very  quickly.  When  other  condi- 
tions were  unfavorable  it  was  often  found  that  some  were  sustained 
by  feeding  upon  the  bodies  of  their  dead  associates,  which  were  com- 
pletely devoured.  The  molted  skins  were  generally  devoured. 

Experiments  with  the  cattle  tick  (B oophilus  annulatus  Say)  and 
its  eggs  evidenced  the  fact  that  the  sowbugs  fed  on  the  dead  ticks  and 
ate  the  eggs  when  no  other  food  was  present.  Thirty-eight  sowbugs 
wrere  furnished  with  a large  number  of  eggs  of  the  tick,  and  it  was 
found  that  in  several  instances  as  many  as  13  tick  eggs  each  were 
eaten  per  day  for  a series  of  days.  This,  however,  was  a maximum, 
the  average  during  the  conduct  of  the  experiment  being  about  3 eggs 
per  day  each.  Experiments  to  find  whether  the  sowbugs  fed  upon 
the  pupae  of  a cutworm  ( Prodenia  ornithogatti  Guen.)  proved  futile. 

A series  of  outdoor  tests  was  also  conducted  with  baits  to  find 
what  substances  might  be  used  to  attract  these  crustaceans,  and 
finally  a series  of  poison  tests  to  ascertain  the  most  advisable  remedy. 

Bread  proved  attractive,  but  as  every  piece  tried  was  carried  away 
by  some  mammal  or  bird  its  use  seemed  inadvisable.  Flour,  bacon, 
potatoes,  radishes,  and  sugar  proved  to  be  good  baits.  To  ascertain 
the  relative  value  of  different  insecticides  several  poison  tests  were 
conducted  with  pyrethrum,  Paris  green,  London  purple,  and  arsenic. 
Few  dead  sowbugs  were  found,  however,  and  it  was  noticed  that  a 


18  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU — IX. 


less  number  approached  the  poisoned  baits  than  those  not  poisoned. 
A series  of  tests  with  repellents  showed  that  barriers  of  powder — 
whether  pyrethrum,  arsenic,  London  purple,  or  Paris  green— proved 
obnoxious,  the  sowbugs  quickly  turning  away  to  avoid  the  danger,  and 
showing,  by  the  frantic  waving  of  the  antennae,  that  they  had  a per- 
ception of  something  wrong.  London  purple  seemed  the  least  repel- 
lent and  yet  practically  as  effective  as  any  of  the  others.  Sowbugs 
placed  in  a jar  with  a biscuit  rolled  in  arsenic  became  frantic  and 
died  in  a few  minutes,  as  did  others  placed  in  jars  with  earth  mixed 
with  either  London  purple  or  Paris  green. 

After  sprinkling  Paris  green  under  boards  which  had  been  favorite 
haunts  of  the  sowbugs,  no  more  live  specimens  could  be  found, 
although  each  day  several  dead  ones  were  discovered.  In  April, 
when  the  sowbugs  were  doing  considerable  damage  to  the  cotton,  a 
mixture  Nof  Paris  green  and  lime  was  dusted  on  and  around  the 
sprouts  with  the  result  that  under  the  poisoned  plants  great  numbers 
of  dead  sowbugs  were  found.  Xo  dead  could  be  found  around  the 
unpoisoned  plants.  The  dusting  was  harsh  treatment  for  the  plants, 
being  in  many  cases  fatal.  It  is,  however,  as  proved  by  other  tests, 
unnecessary  to  dust  the  plants.  The  poison  will  be  picked  up  by  the 
sowbugs  in  foraging  over  the  ground. 

Under  a roll  of  wire  matting  in  his  back  yard  the  writer  found  the 
sowbugs  so  abundant  that  they  crawled  over  each  other  in  their  haste 
to  get  away.  Having  very  little  poison  on  hand,  he  sprinkled  what 
he  had  of  Paris  green,  London  purple,  and  arsenic  over  the  ground  in 
an  area  of  about  1 square  yard  and  rolled  back  the  matting.  Xext 
morning  he  found  21  sowbugs  alive  and  over  800  dead.  Those  alive 
died  in  a few  days,  apparently  from  the  effects  of  the  poisoning. 
The  poison* washed  from  these  dead  sowbugs  and  used  to  saturate  the 
soil  in  jars  in  several  experiments  proved  fatal  to  all  sowbugs  placed 
in  the  jars. 

Kerosene  emulsion  as  a contact  spray  was  fatal.  In  spraying  a 
water  barrel  with  kerosene  the  writer  generally  sprayed  the  ground 
around  it  also,  with  the  result  that  the  sowbugs  were  always  killed. 

These  experiments  and  tests  were  supplemented  by  numerous  ob- 
servations of  actual  conditions  from  which  also  data  may  be  derived 
regarding  means  of  control. 

Concerning  the  plant-feeding  habits,  definite  proofs  were  obtained 
as  follows: 

May  25,  at  7.30  a.  m.,  sowbugs  were  noted  at  various  distances 
above  the  ground  feeding  on  the  foliage  of  weeds  and  honeysuckle. 
On  June  30,  at  7 a.  m.,  three  sowbugs  were  discovered  feeding  on 
weeds,  and  one  at  8 feet  above  the  ground  feeding  on  a honey- 
suckle leaf.  Nine  others  were  found  on  the  honeysuckle  vine  at  var- 
ious heights  up  to  3 feet;  also  two  on  grass  blades  and  seven  on  the 


ECONOMIC  IMPORTANCE  OF  SOWBUGS. 


19 


ground  under  the  honeysuckle.  On  July  3,  at  7.30  p.  m.,  the  sowbugs 
were  just  commencing  to  climb  the  various  plants,  and  none  were 
feeding  as  yet.  On  the  honeysuckle  19  were  seen  at  various  heights 
up  to  3 feet,  and  all  but  twTo  on  the  stems  and  moving  upward. 

The  following  definite  proofs  of  the  scavenger  habits  of  this  sow- 
bug  were  obtained : May  17  a dead  rat  near  the  house  was  found 
covered  with  a great  number  of  sowbugs  and  almost  entirely  eaten, 
even  the  skin  being  eaten  in  places.  At  another  time  several  sowbugs 
were  discovered  diligently  cleaning  a peach  pit. 

Concerning  the  haunts  of  these  animals  the  following  observations 
were  made : In  April  and  May  there  was  considerable  moisture,  and 
under  every  shaded,  moist  board,  cinder,  and  clod,  and  under  straw, 
refuse,  garbage,  and  carrion,  one  could  easily  find  many  adult  sow- 
bugs and  multitudes  of  young.  In  the  cotton  patch,  at  the  base  of 
each  plant,  the  ground  became  cracked,  and  here  sheltered  great  num- 
bers of  sowbugs,  which  very  likely  did  injury  to  the  roots.  May  17, 
under  the  trees  and  in  shady  places,  the  sowbugs  were  so  plentiful 
that  at  every  step  numbers  were  crushed.  July  3,  at  8 p.  m.,  sowbugs 
to  the  number  of  14  were  found  on  an  oak  tree,  the  highest  being  5 or 
6 feet  above  the  ground.  July  26,  in  the  late  afternoon  and  early  even- 
ing, some  five  dozen  sowbugs  were  found  in  cracks  and  holes  on  three 
trees,  many  of  them  as  high  as  could  be  seen. 

Regarding  the  effect  of  natural  and  field  conditions  upon  these 
crustaceans  certain  notes  were  made.  Susceptibility  to  varying 
weather  conditions  was  very  noticeable.  May  25,  at  7.30  a.  m., 
a large  number  of  sowbugs  had  gathered  at  baits.  At  8 o’clock  a 
sudden  storm  commenced  to  rise.  The  sowbugs  seemed  immediately 
conscious  of  danger  and  hastened  in  all  directions  for  the  highest 
shelter  possible,  gaining  protection  on  the  fence  and  beneath  the 
clapboards  of  the  house.  All  were  out  of  sight  when  the  first  drops 
of  water  fell.  In  April  and  May  there  was  considerable  rain,  and 
during  the  periods  of  sunshine,  at  whatever  time  of  day,  the  sow- 
bugs were  to  be  seen  everywhere,  crawling  over  the  sidewalks  and 
pavements.  April  23  and  24  the  ground  was  drenched  with  water, 
and  on  the  25th  dead  sowbugs  were  to  be  found  everywhere  on  the 
ground  and  on  the  sidewalks.  On  June  3 a similar  observation  was 
made  in  a spot  where  the  water  had  stood  for  several  days.  By 
June  15  the  intense  heat  had  driven  the  sowbugs  from  the  open  so 
that  few  could  be  found  in  unprotected  places. 

The  writer’s  notes  upon  the  biology  of  the  isopods  are  based  on 
observations  of  about  a thousand  individuals  in  the  large  series  of 
experiments  that  has  been  already  referred  to. 

Copulation  was  frequently  noted  out  of  doors  during  April  and 
May.  The  males  may  be  distinguished  from  the  females  by  their 
colors  as  well  as  by  the  specific  sexual  characters.  They  are  a 


20  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


dark  slaty  blue,  while  the  females  are  lighter  and  have  yellow 
markings. 

The  period  of  incubation  in  this  species  is  long,  between  fifty-six 
and  ninety-three  days,  according  to  the  varying  results  obtained. 
As  no  individuals  wTere  secured  in  copula,  the  exact  time  of  its  dura- 
tion was  not  recorded.  The  development  of  the  eggs  may  be  watched 
from  the  exterior.  The  females  should  be  treated  very  carefully, 
but  with  a lens  one  may  see  on  the  ventral  side,  in  the  marsupium, 
the  distinct  form  of  the  eggs,  and  may  notice  the  increase  in  size 
and  finally  note  the  young  embryos  and  the  little  white  young.  One 
experiment  with  10  females  was  most  fruitful  in  giving  data  on  this 
point.  On  May  8,  June  16,  and  July  8 young  had  been  produced, 
and  on  examination  on  July  26  all  were  found  to  be  unfertilized 
except  one,  which  had  eggs  apparent.  On  August  7 the  fertile 
female  produced  a brood  of  young.  This  was  ninety-three  days 
after  being  placed  in  captivity.  A male  wTas  admitted  on  July  26, 
and  on  September  30  a brood  of  young  was  produced.  This  would  in- 
dicate a period  of  incubation  of,  at  the  most,  sixty-eight  days.  In 
another  experiment  a female  which  had  just  produced  a brood  of 
young  was  placed  with  3 males  on  August  7.  On  October  2 a brood 
of  young  was  produced,  making  the  period  of  incubation  fifty-seven 
days.  The  number  of  young  in  a brood  varied  from  29  to  79. 

The  little  isopods  are  pure  white  when  they  leave  the  marsupium. 
They  have  six  pairs  of  legs.  AVithin  twenty-four  hours  of  birth  they 
molt,  and  still  have  only  six  pairs  of  legs.  Between  the  fourteenth 
and  eighteenth  days  another  molt  takes  place  and  the  resulting- 
third  instar  has  seven  pairs  of  legs.  The  young  continue  to  grow 
and  molt,  having  been  observed  in  the  act  of  molting  on  the  twenty- 
eighth,  thirty-sixth,  fifty-eighth,  and  sixty-eighth  days.  After  the 
first  molt  there  is  no  regularity  as  to  times  of  molting  in  the  brood, 
all  depending  on  the  food  supply.  After  the  first  molt  a slight  dark- 
ening of  the  intestines  is  noted,  and  by  the  twenty-first  day  the  sow- 
bugs  are  of  a gray  color  throughout  and  under  3 mm.  in  length.  In 
fifty-eight  days  they  have  not  increased  beyond  4 mm.  in  length.  The 
greatest  size  of  any  found  was  15  mm.  This  specimen  was  probably 
several  years  old.  Females  not  over  7 mm.  long  are  capable  of 
reproduction. 

Before  molting,  the  body  of  all  sowbugs  becomes  a very  dirty 
gray  color.  The  act  of  molting  is  peculiar.  At  first  a white  border 
indicating  the  loosening  of  the  old  skin  appears  at  the  front  edge 
of  the  fifth  free  thoracic  segment,  then  another  on  the  sixth,  and 
still  another  on  the  seventh.  Finally  the  entire  posterior  half  of  the 
skin  is  free  and  the  isopod  steps  out  of  it.  This  process  consumes 
about  twenty-four  hours,  and  when  completed  the  posterior  part 
of  the  body  is  of  fresh  slate  color,  while  the  old  anterior  part  appears 


ECONOMIC  IMPORTANCE  OF  SOWBUGS. 


21 


very  dull.  Following  the  first  stage  of  the  molt  the  anterior  seg- 
ments commence  to  loosen  and  are  slid  forward.  The  dorsum  of 
the  third  and  fourth  thoracic  segments  is  loosened  before  the  legs 
of  these  segments  are  released.  From  then  on  the  last  two  pairs  of 
legs  in  the  very  young  and  the  last  three  in  later  stages  are  used  to 
hold  the  animal  in  position.  The  anterior  legs  are  not  available  for 
use  for  some  time  after  they  are  free.  The  antennae  are  withdrawn 
last. 

Regeneration  of  parts  takes  place  in  the  antennae  and  legs.  Several 
times  individuals  with  aborted  members  were  noticed.  These  latter 
would  gradually  attain  full  length,  then  budding  of  the  succeeding 
segment  wTould  be  noted  and  finally  this  member  would  be  normal. 
The  regenerated  part  is  white  for  some  time. 

REMEDIES. 

In  the  treatment  of  sowTbugs  poisoned  baits  are  standard  remedies. 
The  great  fondness  of  sowbugs  for  potatoes  long  ago  led  to  these 
being  used,  poisoned  either  with  Paris  green  or  London  purple. 
The  potatoes  are  sliced  and  a thin  covering  of  powder  applied. 
Sprinkling  the  soil  around  an  injured  plant  with  Paris  green,  or 
dusting  the  same  under  boards  and  other  haunts  of  the  sowbugs  is 
also  very  effective.  If  the  sowbugs  are  injurious  in  a garden  patch — 
after  treating  the  ordinary  haunts — it  is  best  to  keep  the  ground  well 
broken  and  raked  to  prevent  clodding  and  cracking,  which  gives  them 
protection.  Old  boards,  cans,  and  rubbish  should  not  be  allowed  to 
accumulate.  Such  precautions  will  tend  greatly  to  prevent  any 
great  damage  or  annoyance. 

Carbon  bisulphid  has  been  recommended  for  the  treatment  of  sow- 
bugs in  greenhouses  and  dwellings,  but  no  special  experiments  along 
this  line  have  been  tried  by  the  writer. 

PORCELLIO  LiEVIS  Latr. 

Porcellio  Icevis  Latr.  is  a lighter  colored  sowbug  than  the  preced- 
ing, and  does  not  roll  up  in  a ball  when  disturbed,  but  instead  runs 
rapidly  away  to  cover.  The  only  definite  point  in  favor  of  consid- 
ering it  as  naturally  a plant  feeder  was  the  discovery  of  one  dead 
specimen  under  cotton  dusted  with  Paris  green.  It  was  found,  how- 
ever, that  the  best  way  to  keep  this  species  alive  in  the  laboratory 
was  to  furnish  it  with  fresh  cotton  leaves  and  loose  mixed  soil. 
Sowbugs  of  this  species  were  not  found  far  from  the  barns,  and  were 
not  numerous  in  the  laboratory  cotton  patch.  They  were  generally 
under  moist,  dark  objects  and  seemed  to  prefer  damp  wood  piles. 
Several  were  found  with  Armadillidium  in  crevices  and  in  trees  at 
various  heights.  One  Porcellio  was  found  in  the  skeleton  of  a car- 
abid  beetle,  which  was  entirely  eaten  out.  In  numerous  cases  this 


22  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

species  was  found  devouring  those  of  its  own  kind.  The  molted  skin 
is  usually  eaten.  A chest  of  old  clothes,  which  had  been  wet  in  a 
flood,  was  found  to  be  literally  alive  with  this  sowbug.  Experiments 
with  eggs  of  the  cattle  tick  (Boophilus  armulatus  Say)  gave  the  fol- 
lowing results:  Four  sowbugs  provided  with  over  300  eggs  devoured 
153  at  the  rate  of  between  5 and  6 a day  each. 

The  broods  of  this  species  are  small,  numbering  from  8 to  30. 
Metamorphosis  is  more  rapid  than  in  Armadillidium.  The  seventh 
pair  of  legs  is  attained  before  the  twelfth  daj\  Molting  is  as  in 
Armadillidium. 

The  same  remedies  as  recommended  for  Armadillidium  were  found 
to  be  effective. 


METOPONORTHUS  PRUINOSUS  Brandt. 

M etoponorthus  pruinosus  Brandt  is  a much  rarer  sowbug  than 
either  of  the  two  preceding  species.  It  is  also  more  delicate  and  more 
agile.  The  color  is  a beautiful  blue-grav  in  the  male  and  somewhat 
tinged  with  red  in  the  female.  Its  haunts  are  damp,  earthy  places 
in  sheds,  etc. 

These  sowbugs  feed  very  eagerly  on  cotton  leaves  and  were  kept 
under  the  same  condition  as  the  two  preceding  species.  Forty  tick 
eggs  were  eaten  by  two  individuals  at  the  rate  of  about  7 per  day 
each.  They  may  be  poisoned  by  dusting  the  soil  in  their  haunts 
with  arsenicals. 

Reproduction  and  development  is  very  rapid,  much  more  so  than 
in  either  Armadillidium  or  Forcellio.  One  pair  produced  four 
broods  of  young  in  sixty-two  days,  there  being  seventeen,  sixteen, 
and  twenty-one  days  between  broods.  The  broods  are  small.  The 
young  grow  so  rapidly  that  in  two  months  they  are  one-half  as  large 
as  their  parents.  They  molt  frequently.  It  is  very  difficult  to  ob- 
serve this  species  closely  because  of  its  rapidity  of  movement. 

CONCLUSIONS. 

In  conclusion  it  may  be  said  that  (1)  in  a damp  year  the  sowbugs 
may  do  considerable  damage  to  the  young  growing  vegetable  crops; 
(2)  they  serve  at  all  times  as  scavengers;  (3)  their  exclusion  from 
houses  is  advisable  because  of  the  scavenger  habit,  there  being  a 
possibility  of  the  transmission  of  diseases;  (4)  in  the  case  of  the 
cattle-tick  problem  they  may  be  beneficial  by  eating  such  eggs  as  are 
deposited  in  barns,  sheds,  jiens,  in  the  woods  near  the  watering  places, 
and  in  moist  meadows.  Finally,  cleanliness  is  probably  the  best  pre- 
ventive against  sowbug  inroads,  arsenical  compounds  the  best  outdoor 
remedies,  and  carbon  bisulphid  the  best  indoor  remedy. 


O 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY-  BULLETIN  No.  64,  Part  III. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— II. 


u 


•UNKIES.” 


BY 

F.  C.  PRATT, 

Special  Field  Agent. 


Issued  April  2,  1907. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1907. 


% 


CONTENTS. 


Page 

Introduction 23 

Ceratopogon  guttipennis I 23 

The  larva 24 

The  pupa 25 

Other  species  of  Ceratopogon 26 

Other  blood-sucking  Chironomidse 28 


ILLUSTRATIONS 


Page. 

Fig.  3.  Ceratopogon  guttipennis:  adult,  larva,  pupa,  details 24 

4.  Ceratopogon  guttipennis:  mouth  parts  of  adult 24 

5.  Ceratopogon  varicolor:  pupa 25 

6.  Ceratopogon  stelli/er:  adult 26 


ii 


U.  S.  D.  A.,  B.  E.  Bill.  04,  Part  III. 


Issued  April  2,  1907. 


SOME  MISCELLANEOUS  RESULTS  OE  THE  WORK 
OE  THE  BUREAU  OE  ENTOMOLOGY— IX. 


NOTES  ON  “ PUNKIES.” 

( Ceratopogon  spp.) 

By  F.  C.  Pratt, 

Special  Field  Agent. 

INTRODUCTION. 

While  in  the  Blue  Ridge  Mountains  near  Bluemont,  Va.,  a few 
years  ago  the  writer  heard  reports  concerning  11  biting  gnats/’  which 
were  said  to  bite  furiously  before  rains.  At  that  time  his  stay  was 
of  short  duration,  and  a dry  summer  prevented  him  from  securing 
specimens.  In  1904,  however,  during  another  visit  to  the  same  local- 
ity one  rainy  week,  July  21-28,  he  was  harassed  by  myriads  of  these 
minute  flies,  which  were  extremely  numerous  and  active  after  as  well 
as  before  rains.  They  proved  to  be  Ceratopogon  guttipennis  Coq., 
one  of  the  smaller  Chironomidse.  Mr.  D.  W.  Coquillett  has  recently 
made  a careful  systematic  study  of  the  specimens  belonging  to  the 
genus  Ceratopogon  contained  in  the  United  States  National  Museum 
collection,  including  those  reared  at  the  insectary  of  this  Department 
and  by  the  writer,  and  the  determinations  of  the,  species  here  men- 
tioned are  his.  The  records  of  these  rearings  are  brought  together  in 
the  present  paper  with  the  addition  of  such  data  as  have  been  commu- 
nicated by  collectors  and  correspondents. 

Prior  to  1902  little  had  been  published  on  any  of  these  pernicious 
insects  beyond  scattered  notices  such  as  were  furnished  in  a previous 
bulletin®  of  this  Bureau,  on  the  bite  of  C.  stellifer  Coq.  in  Texas.  As 
the  bibliographic  references  have  never  been  collected,  the  writer 
has  brought  together  all  data  and  accompanying  illustrations,  with 
such  references  to  the  biting  and  other  habits  of  this  group  as  he  has 
been  able  to  find. 

CERATOPOGON  GUTTIPENNIS  Coq. 

The  flies  of  the  species  Ceratopogon  guttipennis  will  bite  any  exposed 
part  of  the  body,  preferring,  however,  the  hairy  parts.  At  one  time 
25  individuals  were  counted  in  the  hair  on  the  head  of  the  writer’s 
8-year-old  boy  guide  at  Bluemont,  Ya.  They  are  persistent  in  their 
endeavors  to  obtain  blood,  piercing  the  skin  and  filling  up  with  blood 
so  as  almost  to  lose  semblance  to  flies.  In  many  cases  an  itching 

a Bui.  44,  Div.  Ent.,  U.  S.  Dept.  Agrio.,  p.  92,  1904. 

23 


24  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


pimple  results  from  the  punctures,  the  eruptions,  in  appearance, 


Fig.  3. — Ceratopogon  guttipennis:  a,  adult;  b,  head  of  same;  c,  larva;  d,  h'-ad  of  sam;  e,  pupa.  AL 

greatly  enlarged  (original). 


being  very  much  like  the  vesicles  caused  by  contact  with  poison  ivy. 
The  adult  is  a minute  fly  1 mm.  in  length,  appearing  blackish  to  the 
naked  eye,  but  under  a lens  seen  to  be  of  a deep  gray  hue,  with  mot- 
tled wings  (fig.  3).  Its  mouth  parts  are 
illustrated  in  figure  4.  The  species  was 
described  by  Mr.  D.  W.  Coquillett,  ° to 
whose  paper  the  reader  is  referred  for 
descriptions  of  many  species  of  this  genus. 

The  Virginia  punkie  is  the  name  which  the 
writer  would  suggest  for  this  particular 
species,  as  it  may  possibly  be  distinct 
from  the  one  occurring  in  Maine  which 
the  Indians  called  ano-see-um,”  and  which 
is  popularly  known  as  “ punkie, ” the 
latter  name  being  corrupted  according 
to  locality.  The  flies  of  this  species  are 
very  troublesome  to  man  and  domestic 
animals.  If  milking  is  put  off  later  than  usual  in  the  morning, 
they  drive  the  cows  almost  frantic  by  their  persistence,  and  while 
that  process  is  going  on  the  operator,  having  both  hands  engaged, 
is  at  their  mercy. 

THE  LARVA. 

Larvae  were  found  in  the  very  dirty  water  in  holes  in  the  middle  of 
poplar  st  umps,  in  company  with  larvae  of  mosquitoes  (Anopheles  bar- 


Fig.  4.— Ceratopogon  guttipennis: 
Mouth  parts  of  adult.  Highly 
magnified  (original). 


?rotv U.  S.  Nat.  Mus.,  Vol.  XXIII,  No.  1225,  p.  003,  1901. 


NOTES  ON  “PUNKIES. 


25 


beri  Coq.,  Culex  signifer  Coq.,  and  C.  triseriatus  Coq.),  larvae  of  the 
dascyllid  beetle  Prionocyphon  discoideus  Say,  and  a rat-tailed  maggot 
related  to  Eristalis.  Eggs  could  not  be  found  on  account  of  the 
dirty  condition  of  the  water.  The  larval  food  seems  to  be  the  debris 
at  the  bottom  of  the  holes,  as  well  as  dead  mosquito  and  other  larvae, 
and  cast  larval  and  pupal  skins.  In  one  instance  the  larvae  had 
accomplished  the  complete  disintegration  of  a rat-tailed  maggot,  and 
the  writer  has  seen  them  render  the  skin  of  the  beetle  larva  just  re- 
ferred to  transparent.  On  several  occasions  larvae  were  seen  inside 
the  skin.  They  were  taken  also  at  Woodstock  under  similar  con- 
ditions, that  is,  in  holes  containing  water  in  living  trees. 

The  larva  (fig.  3,  c ),  when  full  grown,  is  4.7  mm.  in  length  and  very 
slender.  It  has  12  segments  exclusive  of  the  head,  the  two  segments 
following  the  head  together  being  about  the  length  of  each  of  the 
other  segments.  It  is  white  in  color,  threadlike,  and  has  a brownish 
head.  Locomotion  is  undulatory.  The  larvae  frequently  come  to 
the  surface  and  then  descend,  squirming  along  the  bottom 
of  a jar  and  apparently  never  remaining  quiet,  as  does  the 
larva  of  Culex  at  times.  Some  of  the  larvae  were  carried 
through  the  winter  in  a room  which  was  moderately  cool, 
but  seldom  near  freezing.  From  these  over- wintered 
larvae  adults  issued  April  27  to  May  8,  1905.  Later  inves- 
tigation may  prove  that  the  larvae  freeze  up  just  as  do  the 
larvae  of  some  mosquitoes,  then  thaw  out  in  the  spring 
and  complete  their  life  cycle. 

THE  PUPA. 

The  pupa  (fig.  3,  e ) is  3.01  mm.  in  length  and  0.84  mm. 
in  breadth.  It  is  of  a brown  color,  a little  more  than 
half  as  long  as  the  mature  larva,  but  much  stouter,  and 
has  eight  abdominal  segments,  each  succeeding  segment 
being  narrowed  to  the  last,  which  is  bifurcated,  the  clasp- 
ers  being  0.35  mm.  in  length.  It  is  provided  with  two 
short  breathing  tubes.  In  this  stage  the  insect  does  not  move  fre- 
quently, remaining  in  a perpendicular  position  in  the  water  just  below 
the  surface.  For  comparison  the  figure  of  an  allied  species,  C. 
varicolor  Coq.  (fig.  5),  from  Bellport,  N.  Y.,  is  reproduced  from  Plate  I, 
Volume  V,  of  the  Proceedings  of  the  Entomological  Society  of 
Washington. 

The  known  distribution,  gathered  from  specimens  in  the  U.  S. 
National  Museum  collection,  is  as  follows:  Plummers  Island,  Md., 
June  6 (H.  S.  Barber);  Medina,  Ohio,  August  5 (J.  S.  Hine);  Blue- 
mont,  Va.,  July  29  and  30,  and  Woodstock,  Va.,  August  8 and  9 (F.  C. 
Pratt);  Santa  Rita  Mountains,  Arizona,  July  8 (E.  A.  Schwarz). 

A specimen  of  Ceratopogon  guttipennis  has  recently  (April  13,  1906) 
been  reared  from  a larva  collected  from  water  in  a hollow  living  tree 


Fig.  5.— Pupa 
of  Ceratopo- 
gon varicolor. 
Much  en- 
larged (after 
Dyar). 


26  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


at  Dallas,  Tex.,  April  9,  1906,  under  conditions  similar  to  those  at 
Bluemont  and  Woodstock,  Va.  This  water  had  been  frozen  during 
the  winter. 

OTHER  SPECIES  OF  CERATOPOGON. 

There  are  nearly  one  hundred  known  species  of  Ceratopogon  repre- 
sented in  the  U.  S.  National  Museum  collection,  and  several  species 
besides  the  one  under  discussion  are  known  to  bite,  among' them 


Fig.  6.— Ceratopogon  stellifer:  Adult.  Highly  magnified  (original). 


C.  sanguisuga  Coq.,  C.  stellifer  Coq.,  0.  variipennis  Coq.,  C.  unicolor 
Coq.,  and  C.  cinctus  Coq.  Many  others  will  undoubtedly  be  found  to 
have  similar  habits. 

C.  sanguisuga  Coq.  has  been  collected  at  the  following  localities: 
Marlboro,  Md.,  May  13  (H.  S.  Barber);  Woodside,  Md.,  October  12 
(J.  E.  Benedict,  jr.) ; Kaslo,  British  Columbia,  June  29  (H.  G.  Dyar). 

C.  stellifer  Coq.  (fig.  6)  is  a little  smaller  than  C.  guttipennis  and  is 
a most  notorious  biter.  Its  distribution,  as  shown  by  specimens  in 
the  U.  S.  National  Museum,  is  as  follows:  District  of  Columbia,  May 
12,  June  6,  September  9 (H.  S.  Barber,  collector) ; Fairfax  County,  Va., 
August  18  (J.  E.  Benedict,  jr.);  Corinth,  Miss.,  August  19,  and 
Athens,  Tenn.,  August  22  (II.  S.  Barber);  Las  Vegas  Hot  Springs,  j 
N.  Mex.,  August  7,  11,  and  19,  and  Hot  Springs,  Ariz.,  June  27  (H.  S.  ( 
Barber). 

C.  variipennis  Coq.  A female  of  this  species  was  collected  while  ji 
sucking  blood  by  W.  P.  Cockerell  at  Las  Vegas,  N.  Mex.,  May,  1902,  ! 
and  has  been  collected  at  Westville,  N.  J.,  in  June,  by  J.  B.  Smith 
and  on  July  2 by  C.  W.  Johnson;  also  at  Richmond,  Va.,  by  Mrs.  ?■ 
A.  T.  Slosson,  and  at  Mexico  City,  Mexico,  by  O.  W.  Barrett. 

C.  unicolor  Coq.  has  been  taken  at  Eureka  and  Fi&ldbrook,  Hum-  |j 
boldt  County,  Cal.,  by  H.  S.  Barber  in  May  and  June. 

C.  cihctus  Coq.  was  found  at  Lake  Worth  and  Biscayne  Bay,  Fla.,| 
by  Mrs.  A.  T.  Slosson;  who  braved  its  biting  in  order  to  collect  speci- j 
mens  of  it. 


NOTES  ON  “PUNKIES.”  27 

C.  websteri  Coq.  was  collected  April  17,  1887,  by  Prof.  F.  M.  Web- 
ster at  Ashwood,  La.,  on  bushes  in  company  with  a species  of  Si- 
mulium. 

C.  mutabilis  Coq.,  reared  from  human  excrement  by  the  writer  in 
the  District  of  Columbia  June  17,  occurs  also  at  Jacksonville,  Fla. 
(Mrs.  A.  T.  Slosson,  collector). 

C.  griseus  Coq.  was  captured  on  human  excrement  by  the  writer  at 
Travilah,  Md.,  in  June.  It  has  been  collected  also  in  Florida  and 
Arizona,  and  Prof.  T.  D.  A.  Cockerell  found  it  on  a horse  at  Pecos, 
N.  Mex.  This  species,  as  well  as  C.  mutabilis,  were  recorded  by 
Dr.  L.  O.  Howard  in  an  article  on  the  insect  fauna  of  human  excre- 
ment as  “Ceratopogon  species.’7  a 

0.  specularis  Coq.  was  reared  by  Mr.  C.  L.  Marlatt  from  horse  and 
cow  manure  during  his  investigation  on  the  horn  fly  ( Hsematobia 
serrata  R.-D.)  in  Virginia  in  1889.  It  has  been  collected  also  at 
Springfield,  Mass.  (Dimmock);  Philadelphia,  Pa.,  June  28,  and 
Natrona,  Pa.,  July  30  (C.  W.  Johnson);  District  of  Columbia,  August 
11  (F.C.  Pratt);  Woodside,  Md.,  October  12  (J.  E.  Benedict,  jr.);  War- 
renton,  Va.,  August  23,  and  Rosslyn,  Va.,  December  30  (C.  L.  Mar- 
latt), and  in  Colorado. 

W.  H.  Longb  found  larvae  of  this  species  on  the  under  side  of  dry 
cow  dung  from  August  to  December,  but  more  abundantly  during 
November  and  December,  in  company  with  C.  brumalis  at  Austin, 
Tex. 

C.  brumalis  Long.  Mr.  W.  H.  Long  writes  of  this  species  as  fol- 
lows: c- 

During  November,  December,  and  January  the  larvae  of  this  species  were  found  in 
immense  numbers  on  the  under  side  of  nearly  dry  cow  dung.  They  seem  to  feed  on 
the  dung,  never  penetrating  very  far  into  the  substance.  Mo  eggs  were  found.  The 
duration  of  the  larval  stage  seems  to  be  several  weeks,  that  of  the  pupal  stage  seven 
to  ten  days.  * * * Several  hundred  larvae  of  all  ages  were  found  on  the  under 
surface  of  a piece  of  moist  rotting  elm  wood;  similar  larvae  and  puparia  were  also 
found  in  the  nests  of  the  common  foraging  ant  ( Eciton  coecum ) on  several  different 
occasions. 

Mr.  Long  states  that  he  reared  imagines  from  larvae  taken  in  these 
various  situations  and  they  proved  to  be  the  same  species.  It  is 
known  from  Austin,  Tex. 

C.  stenammatis  Long.  Long  writes  of  this  species  as  follows  :d 

The  specimens  were  received  from  Dr.  W.  M.  Wheeler,  who  found  them  in  the  nest 
of  an  ant  ( Stenamma  fulvum  subsp.  aquia)  at  Colebrook,  Conn.,  August,  1900.  They 
were  moving  about  in  the  refuse  heaped  up  by  the  ants  in  certain  portions  of  their 
nests.  The.  species  seems  to  be  a genuine  myrmecophile  like  the  European  species 
(C.  Braueri  Wasmann). 

a Proc.  Wash.  Acad.  Sci.,  Yol.  II,  p.  559,  1900. 

&Biol.  Bui.,  Vol.  Ill,  pp.  7-10,  figs.  3-6  (in  part),  1902. 

CL.  c.,  Vol.  Ill,  pp.  3-7,  figs.  1,  2,  6 (in  part). 

d L.  c.,  p.  10,  figs.  4,  6 (in  part). 


28  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


C.  texanus  Long. 

The  larvae  of  this  species  are  gregarious  in  small  numbers  beneath  the  bark  of  old 
dead  trees  in  moist  places,  or  on  the  under  side  of  very  damp  rotting  wood  during 
December  and  January.  Rare.a 

Austin,  Tex. 

C.  wheeleri  Long.  Adults  of  this  species  have  not  been  reared  on 
account  of  a proctotrypid  parasite  ( Adeliopria  longii  Ashm.). 

The  Ceratopogon  puparia  were  found  December  15,  1900,  beneath  a stone,  in  what 
seemed  to  be  an  abandoned  ant’s  nest.  The  parasites  issued,  one  from  the  thoracic 
dorsum  of  each  of  the  Ceratopogon  puparia  December  31  and  lived  eight  or  ten  days.& 

Austin,  Tex. 

The  late  Dr.  O.  Lugger0  calls  attention  to  the  “cussedness”  of 
an  unidentified  species  and  gives  a figure  which  may  possibly  be  C. 
stellifer.  Ceratopogon  has  also  been  recorded  as  breeding  under 
leaves  and  in  flowing  sap  from  trees;  thus  the  group  is  seen  to  have 
diversified  habits. 

In  Europe,  Professor  Mikd  described  as  Ceratopogon  Jiippocastani 
a liairy-winged  species  having  a footless  larva,  found  in  the  very 
moist  or  wet  ulcerous  parts  of  stems  of  horse-chestnut  (JZsculus 
hippocastanum ) . 

OTHER  BLOOD-SUCKING  CHIRONOMID^. 

A related  form  which  may  be  mistaken  for  Ceratopogon  is  CEcacta 
furens  Poey,  taken  in  June  at  Cardenas,  Cuba,  by  Mr.  E.  A.  Schwarz, 
and  at  Montserrat,  West  Indies,  April  8,  by  Mr.  H.  G.  Hubbard.  It 
was  also  taken  at  Perihueta  and  Laguna  Carmen,  Mexico,  by  Dr. 
Alfredo  Duges. 

Another  related  fojrn,  Tersesthes  torrens  Towns.,  described  by  Prof. 
C.  H.  T.  Townsend 0 with  notes  on  habits,  has  been  collected  at  the 
following  localities:  Filmore  Canyon,  and  Las  Vegas  Hot  Springs, 
N.  Mex.  (Townsend);  Fort  Grant,  Ariz.,  July  19  (H.  G.  Hubbard); 
Ash  Fork,  Ariz.,  June  18  (H.  S.  Barber);  Lake  Worth,  Fla.  (Mrs. 
A.  T.  Slosson);  Salt  Lake,  Utah  (H.  S.  Barber),  and  Baracoa,  Cuba, 
August  (A.  Busck). 

Mr.  Barber  has  collected  from  thirty  to  forty  species  of  Ceratopogon  | 
and  states  that  Tersesthes  is  much  worse  as  a pest  than  any  Cera- 
topogon he  has  ever  encountered. 

« Long.  L.  c.,  pp.  10-12,  figs.  5,  6 (in  part). 

b Long.  L.  c.,  pp.  12-14,  fig.  5 (in  part). 

c Second  Rept.  Ent.  of  Minn.  Exp.  Sta.,  pp.  171-172,  fig.  142,  1896. 

d Wiener  Ent.  Ziet.,  Vol.  VII,  pp.  183-192,  PI.  II,  1888. 

* Psyche,  Vol.  VI,  pp.  369-371,  pi.  8,  1893. 


o 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 
BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  IV. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


AN  INJURIOUS  NORTH  AMERICAN  SPECIES 
OF  APION,  WITH  NOTES  ON 
RELATED  FORMS. 


F.  H.  CHITTENDEN, 

Entomologist  in  Charge  of  Breeding  Experiments. 


Issued  January  14,  1908. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE 

1908. 


CONTENTS. 


Page. 

Apion  griseum  Sm 29 

Apiori  colon  Sharp 30 

Notes  on  related  forms 31 

Apion  ccncipcnne  Sm 31 

Apion  turbulcntuni  Sm 31 

Apion  cribricolle  Lee 31 

Apion  proclive  Lee 31 

Apion  patruele  Sm 31 

Apion  segnipes  Say 31 

Apion  decoloratum  Sm 31 

Apion  lierculanum  Sm 32 


ILLUSTRATION 


Page. 

Fig.  7.  Apion  as  si  mile 30 

ii 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  IV. 


Issued  January  14,  1908. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


AN  INJURIOUS  NORTH  AMERICAN  SPECIES  OF  APION,  WITH 
NOTES  ON  RELATED  FORMS. 

By  F.  H.  Chittenden, 

Entomologist  in  Charge  of  Breeding  Experiments. 

In  economic  works  of  European  authors  a very  considerable  number 
of  species  of  Apion  are  mentioned  in  connection  with  injuries  to  cul- 
tivated plants,  and  particularly  to  the  Papilionacese,  for  which  a 
large  proportion  of  species  show  a preference.  Certain  European 
forms  are  sufficiently  abundant  to  receive  common  English  names, 
among  which  are  the  clover  weevil,  the  Dutch-clover  yellow-legged 
weevil,  the  cinquefoil  weevil,  the  tare  or  vetch  weevil,  and  others, 
the  popular  name  being  indicative  of  each  insect’s  food  habits. 

None  of  our  native  species,  so  far  as  known  to  the  writer,  has  hith- 
erto been  recorded  as  injuring  useful  plants;  hence  a note  received 
from  Mr.  James  K.  Metcalfe,  Silver  City,  N.  Mex.,  of  injuries  to  for- 
age plants  by  Apion  griseum  Sm.  is  of  interest. 

APION  GRISEUM  Sm. 

September  25,  1899,  our  correspondent  sent  seedpods  of  the  Met- 
calfe bean  ( Phaseolus  retusus ),  together  with  specimens  of  the  beetle. 
This  weevil  was  stated  to  be  very  destructive  to  this  plant,  which  has 
been  mentioned  by  Dr.  Jared  G.  Smith  as  one  of  the  most  promising 
of  our  native  forage  plants.®  The  weevil  was  said  to  be  also  destruc- 
tive to  the  “ Raphael  ” bean  ( Phaseolus  wrightii) , and  we  have 
received  the  same  species  from  Phaseolus  beans  from  Tolima,  Mexico. 

This  species  has  also  been  observed  by  the  writer  to  develop  in  the 
seedpods  of  a wild  bean,  Phaseolus  polystachyus  ( perennis ).  Eight- 
een individuals  were  found  on  opening  a pod  of  this  plant  at  Ross- 
lyn,  Va.,  April  22.  One  seed  had  harbored  eleven  Apions,  all  of 
which  perished  owing  to  their  inability  to  escape  from  the  pod, 

® Yearbook,  U.  S.  Department  of  Agriculture,  for  1897,  p.  506. 


29 


30 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


which  had  evidently  died  prematurely  as  a result  of  overinfestation 
by  the  weevils.  Pods  were  examined  during  the  first  week  of  October, 
and  at  this  time  half  of  those  gathered  were  infested.  The  sound 
pods  may  be  easily  separated  from  the  infested  ones,  since  the  latter 
are  flattened,  discolored,  and  sometimes  even  distorted,  while  sound 
and  fully  matured  pods  are  full  and  round  like  a diminutive  pea-pod. 
Most  individuals  were  in  the  pupal  condition  at  the  last-mentioned 
period.  The  adults,  like  others  of  the  genus,  feed  upon  the  leaves, 
piercing  them  with  innumerable  holes,  from  20  to  as  many  as  60  such 
punctures  being  sometimes  visible  on  a single  small  leaf. 

The  insect  hibernates  in  the  beetle  condition,  escapes  from  the  pod 
about  May  or  June,  or  earlier  if  the  pod  happens  to  crack,  and  the 
punctures  made  upon  the  early  appearance  of  the  insect  are  plainly 
visible  in  October. 

Careful  comparison  of  the  writer’s  reared  material  of  Apion  griseum 
with  typical  specimens  in  the  U.  S.  National  Museum  (some  of  which 
appear  to  be  types)  of  A.  fraternum , identified  as  such  by  Dr.  J.  B. 
Smith,  who  described  that  species,  shows  that  this  is  the  same  insect 
which  was  found  by  Dr.  C.  V.  Riley  on  Strophostyles  ( Phaseolus ) 
pauciflora  as  cited  by  Smith.  The  identity  of  these  two  forms  has 
also  been  recognized  by  Fall  in  his  revision  of  the  genus.® 

The  chalcidid  fly  Catolaccus  incertus  Ashm.  was  reared  from  in- 
fested pods,  and  is  undoubtedly  parasitic  on  this  Apion. 

APION  COLON  Sharp. 

February  6,  1903,  Dr.  Edward  Palmer  furnished  specimens  of  this 
species  collected  at  Alvarez,  San  Luis  Potosi,  Mexico,  on  a species  of 
wild  bean  with  scarlet  flowers  and  tuberous 
roots,  which  is  used  as  a cure  for  hydrophobia 
(Palmer’s  No.  63). 

This  species  is  not  known  to  occur  in  our  lim- 
its, but  is  mentioned  because  of  possible  economic 
importance. 

The  accompanying  illustration  (fig.  7)  repre- 
sents a European  species,  and  will  assist  the  av- 
erage student  of  entomology  in  recognizing  wee- 
vils of  the  genus.  Upward  of  100  species  of  the 
genus  Apion  have  been  recognized  in  America 
north  of  Mexico,  and  most  of  these  are  minute 
or  almost  microscopic.  Tt  follows,  therefore,  as 
there  is  considerable  generic  resemblance  throughout,  that  these 
many  different  forms  are  difficult  of  differentiation,  both  sexes  being 
frequently  required  to  make  specific  determination.  The  body  is 

"Trans.  Amer.  Ent.  Sot\,  Vol.  XXV,  p.  147,  1898. 


Fig.  7. — Apion  assi- 
mile,  greatly  en- 
larged. 


AN  INJURIOUS  NORTH  AMERICAN  APION,  ETC. 


31 


elongate  pyriform,  or  pear-shaped;  the  rostrum  or  beak  is  more  or 
less  prolonged  in  front  of  the  eyes,  and  the  head  back  of  the  eyes  is 
usually  constricted,  forming  a neck.  The  antennae  are  delicate  and 
elbowed. 

NOTES  ON  RELATED  FORMS. 

The  following  observations  on  other  species  of  Apion  are  chiefly 
from  the  writer’s  personal  experience,  and  all  rearings  should  be  so 
credited,  with  the  exception  of  those  where  the  collector  or  observer 
is  mentioned : 

Apion  ceneipenne  Sm. — During  the  first  two  weeks  of  June  nu- 
merous examples  of  this  species  were  obtained  at  Rosslyn,  Va.,  by 
beating  a common  tick-trefoil  (Meibomia  [Desmodium] ).  When 
the  beetles  were  confined  with  leaves  they  riddled  them  with  minute 
holes  after  the  manner  of  the  commoner  A.  nigrum  on  locust. 

Apion  turbulentum  Sm. — This  species  was  observed  during  the 
latter  half  of  September  in  and  near  Cabin  John,  Md.,  and  in  con- 
siderable numbers  on  Meibomia  marylandica.  The  beetles  were 
numerous,  occurring  on  the  seeds,  in  which  they  undoubtedly  live, 
although  they  were  not  reared. 

Apion  cribricolle  Lee. — We  have,  among  the  Department  notes, 
one  on  the  rearing  of  this  beetle  from  a species  of  lotus  ( Lotus 
\Ilosackid\  glabra)  from  Henwood,  Santa  Cruz  County,  Cal. 

Apion  proelive  Lee. — July  18,  189S,  Mr.  E.  M.  Ehrhorn  reported 
that  this  species  was  infesting  the  pods  of  Lupinus  arborea  at  Pacific 
Grove,  Cal.,  where  nearly  every  pod  showed  signs  of  attack.  A 
similar  attack  to  lupine  was  reported  by  Mr.  Ehrhorn  in  1907  at 
San  Francisco,  Cal.  The  beetles  issued  September  5-19.  The  species 
proves  to  be  parasitized  by  a chalcidid. 

Apion  patruele  Sm. — This  species  was  found  abundantly  on  a 
climbing  wild  legume  at  Cold  Spring  Harbor,  Long  Island,  N.  Y.,  in 
July.  The  plant  at  this  time  was  in  bloom,  and  there  is  little  doubt 
that  the  larva  inhabits  the  pods. 

Apion  segnipes  Say. — The  writer  has  reared  from  this  species, 
found  in  its  well-known  food  plant,  the  goat’s  rue  ( Cracca  \Teph- 
rosia\  virginiana ),  the  chalcidid  parasite  Eurytoma  tylodermatis 
Ashm.,  in  August,  in  Maryland,  near  the  District  of  Columbia.  The 
writer  has  also  reared  this  species  from  its  larva  found  in  the  cells  of 
Tyloderma  foveolatum  in  October.  There  is  fair  indication,  there- 
fore, of  two  generations. 

Apion  decoloratum  Sm. — This  species  breeds  in  the  seed  pods  of 
the  genus  Meibomia.  Beetles  have  been  reared  from  M.  paniculata 
and  M.  grandiflora,  and  exit  holes  have  been  observed  in  pods  of  all 
of  the  species  of  this  genus  of  plants  that  have  come  under  observation 
in  Maryland  and  Virginia  about  Washington.  The  beetles  began 


32  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

issuing  from  the  pods  September  21,  and  most  of  those  in  the  field  had 
escaped  by  the  end  of  the  month.  Stragglers,  however,  continued  to 
issue  from  the  material  gathered  until  the  end  of  October.  Mr.  Fall 
states  that  “ Mr.  Wickham  has  found  the  species  in  some  abundance 
on  Desmodium  in  Iowa  City.”  Catolaccus  incertus  Ashm.  was  reared 
with  this  species. 

Apion  herculanum  Sm.  was  reared  July  24-28  from  the  dried  fruit 
of  sheepberry  ( Viburnum  lentago ),  and  beetles  were  taken  in  the 
same  locality,  Marshall  Hall,  Md.,  in  May  on  V.  acerifolium  in  bloom. 
At  Ithaca,  N.  Y.,  it  was  taken  in  fair  abundance  on  the  flowers  of 
this  same  plant,  collected  May  28,  June  5-20,  and  July  2-6  several 
years  previously.  Mr.  Schwarz  informs  th^  writer  that  he  has 
reared  the  species  also  from  dogwood  ( Cornus  sp.). 


o 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  Y. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY-IX. 


INSECTS  INJURIOUS  TO  THE 
LOCO  WEEDS. 


BY 

F.  H.  CHITTENDEN,  Sc.  D., 

Entomologist  in  Charge  of  Breeding  Experiments. 


Issued  May  29,  1908. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1908. 


CONTENTS. 


Page. 

The  false-indigo  gall-moth  ( Walshia  amorphella  Clem.) __ 34 

The  loco  root-maggot  ( Pegomya  lupini  Coq. ) 35 

The  fickle  midge  ( Sciara  inconstans  Fitch) 36 

The  four-lined  loco  weevil  ( Cleonus  quadrilineatus  Chevr.) 37 

The  yellow  loco  fly  ( Tritoxa  incurva  Loew. ) 38 

The  spotted  root  fly  ( Euxesta  notata  Wied.) 38 

The  bur-clover  aphis  (Aphis  medicaginis  Koch) 40 

The  meal  snout-moth  (Pyralis  farinalis  L. ) 40 

Plant-bugs,  leafhoppers,  etc 41 

Miscellaneous  insects 41 


IL  LUSTRATIONS. 


Page. 

Fig.  8.  The  false-indigo  gall-moth  ( Walshia  amorphella ):  Adult,  larva,  work. . 34 

9.  The  fickle  midge  ( Sciara  inconstans)'.  Adults  and  details,  larva,  pupa..  37 

10.  The  four-lined  loco  weevil  (Cleonus  quadrilineatus):  Adult 37 

11.  The  four-lined  loco  weevil  ( Cleonus  quadrilineatus) : Cocoon 38 

12.  The  spotted  root  fly  (Euxesta  notata) : Adult  male  and  female ..  39 

13.  The  meal  snout-moth  (Pyralis  farinalis):  Adult,  larva  and  details, 

chrysalis  and  details 40 

14.  Bruchus  obsoletus:  Adult  and  details 41 


ii 


r.  S.  D.  A.,  B.  Bui.  64,  Part  V. 


Issued  May  29,  19t  8. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS. 

By  F.  H.  Chittenden,  Sc.  I).. 

Entomologist  in  Charge  of  Breeding  Experiments. 

For  many  years  the  Bureau  of  Entomology  has  conducted  corre- 
spondence in  regard  to  insects  found  on  the  loco  weeds  of  the  semiarid 
regions  of  the  West.  In  earlier  years  these  insects  were  found  chiefly 
on  purple  or  woolly  loco,  Astragalus  mollissimus , and  more  recently 
on  the  white  loco,  Arag alius  lamberti.  It  was  at  one  time  supposed  by 
stockmen  that  the  insects  might  be  the  cause  of  the  poisoning  to  sheep, 
cattle,  and  other  stock,  but  such  is  not  the  case. 

The  general  subject  of  loco  poisoning  to  stock  has  been  treated  in 
various  publications,  but  the  insect  inhabitants  of  the  weeds  have 
never  received  mention  in  this  connection,  with  the  exception  of  the 
false-indigo  gall-moth,0  which  is  apparently  the  principal  insect  de- 
stroyer of  the  loco.  Numbers  of  correspondents  and  observing  bota- 
nists have  noticed  that  the  caterpillar  of  this  insect,  which  feeds  at  the 
roots  and  crowns  of  locos,  is  quite  instrumental  in  reducing  their  abun- 
dance. Recently  Dr.  C.  Dwight  Marsh,  Bureau  of  Plant  Industry, 
has  collected  many  insects  on  locos  and  expresses  the  opinion  that  sev- 
eral other  species  are  concerned  in-  this  work.  Chief  among  these  are 
the  fickle  midge, b the  loco  root-maggot, c the  four-lined  loco  weevil/* 
and  the  spotted  root  fly.e  Of  these  the  root-maggot,  midge,  and  root 
fly  are  probably  in  the  main  attracted  to  the  plants  after  the  gall- 
moth  has  first  caused  injury,  but  the  weevil  also  attacks  living  roots, 
usually,  however,  according  to  observations,  after  the  plant  has  pro- 
duced its  quota  of  seed. 

The  following  account  of  loco  insects  has  been  prepared  from  the 
records  of  the  Bureau  of  Entomology,  much  of  the  material  having 
also  been  supplied  by  Doctor  Marsh,  and  in  the  list  which  follows  it 

d Cleonus  quadrilineatus  Chevr. 
e Euxesta  notata  Wied. 


0 Walshia  amorphella  Clem. 
& Sciara  inconstans  Fitch. 
c Pegomya  lupini  Coq. 


33 


34 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


will  be  understood  that  the  locality  Hugo,  Colo.,  is  the  one  in  which 
he  collected  specimens  for  identification.  This  account  does  not  pre- 
tend to  be  an  exhaustive  one,  but  is  more  in  the  nature  of  a list,  with 
notes  on  such  species  as  appear  to  be  concerned  in  killing  out  the  weed. 
Considering  the  toxic  qualities  of  the  locos,  the  insects  which  affect 
them,  with  some  exceptions,  may  be  classified  as  highly  beneficial, 
since  the  species  which  have  just  been  mentioned  have  in  some  cases 
completely  rid  large  areas  of  loco  weeds. 

THE  FALSE-INDIGO  GALL-MOTH. 

( Walsliia  a morph  ell  a Clem.) 

Prior  to  1886  the  larva  of  this  species  was  known  omy  as  a gall 
maker  on  the  stems  of  false  indigo  ( Amorpha  fruticosa)  and  was 
described  from  moths  reared  from  that  plant  in  1864.  An  account 

of  the  species  and  its 
habits  was  afterwards 
given  by  Riley  in  1870.® 
He  stated  that  as  the 
twigs  invariably  with- 
ered and  died  above  the 
gall,  and  as  the  shrub 
was  of  no  special  value, 
the  species  might  be 
placed  among  our  harm- 
less insects.  In  early 
records  of  the  Bureau 
of  Entomology  there  are 
numerous  references  to 
this  species  and  its  oc- 
currence on  false  indigo. 
In  1886  a second  food  plant,  Astragalus  mollissimus , was  recorded. & 

This  moth  (fig.  8,  a)  belongs  to  the  family  Tineidae  and  has  a wing 
expanse  of  about  half  an  inch.  It  is  grayish  yellow,  spotted  with 
dark  brown,  and  both  wings  are  provided,  as  in  others  of  this  group, 
with  very  long  posterior  fringes,  longer  than  the  wings  themselves. 
The  larva  or  caterpillar  (fig.  8,  b)  is  yellowish  white,  with  the  head 
and  thoracic  plate  dark  brown.  It  measures  from  a third  to  two- 
fifths  of  an  inch  in  length. 

Our  records  of  the  distribution  of  this  species  show  that  it  has  been 
observed  most  commonly  from  Iowa  and  Missouri  westward  to  Cali- 
fornia, although  it  occurs  also  in  the  Atlantic  region.  It  is  quite 


Fig.  8.  — False-indigo  gall-moth  ( Walshia  amorphella ):  a,  Fe- 
male moth;  b,  larva;  c,  gall  in  false  indigo,  showing  exit 
hole  near  top;  d,  gall  opened,  showing  larva  in  situ,  a,  b,  3 
times  natural  size;  d,  c,  natural  size.  (After  Riley.) 


a 2nd  Kept.  State  Ent.  Mo.,  pp.  132-133. 
b Proe.  Ent.  Soc.  Wash.,  Vol.  I,  p.  30. 


INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS. 


85 


singular  that  the  larva  should  have  the  dual  habit  of  forming  galls 
on  a shrub,  as  in  the  case  of  its  occurrence  eastward,  and  at  the  same 
time  boring  into  the  roots  of  weeds,  as  is  its  western  habit.  From 
the  experience  of  many  persons  who  have  been  in  correspondence  with 
this  office  in  regard  to  the  habits  of  this  insect,  there  can  be  no  hesita- 
tion in  reiterating  that  it  is  the  most  potent  element  in  the  destruction 
of  the  loco  weed  of  the  West.  In  this  connection  it  may  be  well  to 
mention  briefly  what  some  of  our  correspondents  liave  reported.  Mr. 
Thomas  J.  Quillian,  Birmingham,  Colo.,  wrote,  April  9.  1889,  that 
from  observations  conducted  by  himself  and  a fellow  stockgrower  he 
was  led  to  believe  that  possibly  the  “ worms  ” eaten  by  the  stock  pro- 
duced the  craziness  (and  sometimes  death)  instead  of  the  plant,  as 
was  generally  supposed,  this  conclusion  being  more  plausible  because 
upon  opening  the  dead  animals  many  “ worms  ” were  always  found. 
Mr.  D.  II.  Marum,  Woodward,  Okla.,  has  written  that  in  that  vicinity 
the  plants  begin  to  die  about  the  last  week  in  May.  At  that  time  the 
small  “ worms  ” are  found  in  the  roots,  which  they  hollow  out  com- 
pletely, leaving  practically  nothing  but  a shell.  He  suggested  the 
possibility  of  propagating  these  and  other  loco  insects  with  a view 
to  destroying  the  weed.  Mr.  Thomas  Carson,  Bovina,  Tex.,  writing 
of  the  great  loss  in  cattle  in  that  section,  stated  that  this  insect,  which 
he  had  observed  devouring  the  heart  of  the  loco,  was  very  efficient  in 
reducing  the  abundance  of  this  noxious  weed  and  had  proved  very 
beneficial  to  the  cattle  interests.  In  closing,  it  should  be  added  that 
in  the  extreme  west,  as,  for  example,  at  Alameda,  Cal.,  this  species  has 
been  observed  breeding  on  Lupinus  arborea . 

THE  LOCO  ROOT-MAGGOT. 

( Pegomya  lupini  Coq.) 

The  loco  root -maggot  has  been  prominent  among  insects  found 
feeding  on  the  roots  of  Astragalus  mollissimus  for  a number  of  years. 
Doctor  Marsh  sa}^s  that  in  the  neighborhood  of  Hugo,  Colo.,  it  is 
apparently  the  most  important  agent  in  the  suppression  of  the  pur- 
ple loco.  It  is  probable  that  it  will  rank  second  to  the  false-indigo 
gall-moth  as  a destroyer  of  this  plant.  On  this  head  Mr.  George 
Hochderffer,  Flagstaff,  Ariz.,  who,  on  April  T,  1907,  sent  specimens 
found  at  the  roots  of  the  plant,  stated  that  hundreds  of  acres  of  loco 
had  been  destroyed  by  this  insect,  and  he  believed  not  only  that  it 
might  prove  to  be  a valuable  friend  to  stockmen,  but  that  it  had 
already  proven  so. 

It  is  the  larva  of  a species  of  anthomyiid  fly  closely  related  to  the 
seed-corn  maggot,®  the  adult  being  readily  distinguished  from  that 


° Pegomya  fusciccps  Zett. 


36 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


of  the  latter  by  the  long  bristles  on  the  underside  of  the  posterior 
femora  or  hind  thighs.  It  was  described  in  1901  from  flies  obtained 
from  the  stems  of  Lupinus  alba  from  Los  Angeles,  Cal.®  This  species 
resembles  the  common  house  fly,  though  more  slender  and  of  a more 
distinctly  gray  color.  The  larvae  are  white  maggots  and  resemble  the 
seed-corn  maggot.  They  infest  chiefly  the  crown  of  the  plant,  seldom, 
if  ever,  entering  the  roots,  but  penetrating  into  the  larger  stems; 
sometimes,  it  is  reported,  going  as  far  as  the  base  of  the  flowers. 

We  have  records  of  the  rearing  of  this  species  from  A.  mollissimus 
from  material  collected  at  Sherlock,  Ivans.,  and  from  Lupinus  arborea 
at  Alameda,  Cal.,  in  April.  In  June,  1887,  it  was  received  from  New 
Mexico  with  statement  by  Dr.  V.  Havard  that  it  was  breeding  in 
the  roots  of  A.  mollissimus.  At  this  time  we  were  conducting  con- 
siderable correspondence  with  Doctor  Havard  in  regard  to  the  insect 
enemies  of  this  plant  in  Kansas,  New  Mexico,  and  Texas.  Doctor 
Havard  stated,  among  other  things,  that  at  that  time  it  was  some- 
what generally  believed  that  “ locoism  ” on  the  part  of  stock  animals 
was  due,  not  to  any  deleterious  property  of  the  plants,  but  to  the 
larvae  of  insects  found  abundantly  in  the  stems  and  roots.  In  all 
specimens  received  by  him  from  New  Mexico  the  stems,  without  ex- 
ception, were  bored  by  the  larvae  of  this  species.  Flies  from  this  last 
lot  began  issuing  June  10.  In  May,  1905,  and  January,  1908,  this 
species  was  again  received  from  locos  from  Hugo,  Colo.  In  that 
locality  it  was  associated  with  Euxesta  notata  and  Sciara  inconstans. 

THE  FICKLE  MIDGE. 

( Sciara  inconstans  Fitch). 

This  minute  gnat-like  fly  was  reared  from  purple  loco  received  from 
Hugo,  Colo.,  in  1906,  the  adults  issuing  May  24.  During  1907-8  addi- 
tional specimens  were  received  from  the  same  source.  Doctor  Marsh 
has  expressed  the  belief  that  this  species,  with  the  larger  maggot,  Pe- 
(jomya  lupini  Coq.,  is  one  of  the  chief  causes  of  the  destruction  and 
apparent  temporary  extermination  of  this  loco  weed  in  that  section 
of  Colorado.  The  members  of  the  family  to  which  it  belongs,  the  ; 
Mycetophilidse,  are  for  the  most  part  scavengers,  feeding  on  decom- 
posing vegetable  matter,  including  fungous  growths,  whence  their  i 
name  of  “ fungus  gnats.”  Taken  as  a whole,  however,  the  family  dis-  j 
plays  great  diversity  in  habits  and  the  present  species  is  the  most  ) 
widely  distributed  and  most  nearly  omnivorous  of  its  kind.  It  feeds 
on  vegetation  of  almost  all  forms,  occurring  destructively  in  green-  . 
houses,  as  also  in  the  open,  in  cultivated  and  uncultivated  regions. 
It  appears  to  be  most  abundant  in  the  Northern  States. 

° Ent.  News,  September,  1001,  pp.  200-207. 


INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS. 


37 


The  insect  is  shown  in  its  different  stages,  highly  magnified,  in 
figure  9.  The  size  is  indicated  by  the  hairlines  at  the  right  of  the 
figure.  It  will  be  noticed  that  the  female  fly  ( c ) is  larger  than  the 


Fig.  9. — Fickle  midge  ( Sciara  inconst ans ) : a,  Male  fly  ; b,  external  genital  organs  of  male  ; 
c,  female  ; d,  enlarged  antennal  joints  of  same  ; e,  maxillary  palpus  of  same  ; f,  tip  of 
abdomen  of  female  from  side  ; g , pupa,  ventral  view  ; h,  larva,  dorsal  view,  a,  c,  g,  h. 
Much  enlarged;  6,  d,  e,  f,  more  enlarged.  (Author's  illustration.) 


male.  The  latter  (a)  is  recognized  by  its  claspers,  shown  much  en- 
larged at  b.  The  larva  is  a delicate,  thread-like  maggot  of  milk-white 
color  with  a jet-black  head.  On  account  of  its  minute  size — about  J 

of  an  inch  in  length — its  presence  is  very 
frequently  unnoticed  in  greenhouses,  al- 
though the  flies  are  more  conspicuous,  from 
their  habit  of  flying  about  on  the  “ glass/’ 
In  some  cases  this  species  is  confused  with 
nematodes  or  eel-worms.® 

THE  FOUR-LINED  LOCO  WEEVIL. 

( Cleonus  quadrilineatus  Clievr. ) 

This  curculionid  weevil  was  found  breed- 
ing in  considerable  numbers  on  Arag alius 


at  Hugo,  Colo.,  during  1907,  by 


‘to 

lamberti 

Dr.  C.  I).  Marsh,  who  reports  very  appre- 
ciable injury.  As  a rule,  however,  this 
species  does  not  occur  in  numbers  until 
after  the  plants  have  made  good  growth 
and  have  seeded. 

This  beetle,  (fig.  10)  measures  about  half  an  inch  in  length;  has  a 
stout  rostrum  or  beak,  a little  shorter  than  the  thorax;  is  black,  and 
densely  coated  with  gray  pubescence  alternating  with  two  pairs  of 
longitudinal  black  lines,  one  subsutural  and  the  other  submarginal. 


Fig.  10.— Four-lined  loco  weevil 
( Cleonus  quadrilineatus ):  Adult. 
Much  enlarged  (original). 


fflA  more  complete  account  of  this  insect  appeared  in  Bui.  27,  n.  s.,  Div.  Ent., 
U.  S.  Dept.  Agric.,  pp.  108-113,  1901. 


38 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Practically  nothing  is  known  of  the  life  history  of  any  species  of 
the  genus,  of  which  there  are  quite  a number.  The  beetles  are  par- 
tial to  Astragalus  and  Aragallus  and  feed  also  on  lupines  and  related 
plants.  The  larvae  are  undoubtedly  root  or  stalk  feeders.  The  pres- 
ent species  in  the  larval  stage  affects  the  roots  and  transforms  in  the 
ground  in  comparatively  large  earthen  cocoons,  such  as  are  shown  in 
the  illustration  (fig.  11). 


Fig.  11. — Four-lined  loco  weevil  ( Cleonus  quadrilineatus)  : Cocoon.  (Original.) 

THE  YELLOW  LOCO  ELY. 

( Tritoxa  incurva  Loew.) 

This  species  was  collected  at  Hugo,  Colo.,  on  Aragallus  lamberti. 
It  is  a two-winged  fly  of  the  family  Ortalidae  and  is  recorded  as 
having  the  same  habits  as  the  black  onion  fly  ( Tritoxa  flexa  Wied.) , 
whose  larva  or  maggot  lives  in  the  bulbs  of  onions ; indeed,  it  was  at 
one  time  considered  a color  variety  of  the  latter.  The  wing  markings 
are  almost  identical,  but  the  face,  thorax,  and  most  of  the  abdomen 
are  brownish  yellow,  whereas  in  the  onion  fly  these  parts  are  black. 
Its  body  is  about  one-third  of  an  inch  long,  each  wing  having  a little 
shorter  measurement.  Neither  species  under  consideration  is,  as  a 
rule,  especially  abundant,  but  both  are  capable  of  being  very  destruc- 
tive to  plant  life  when  they  multiply  in  numbers,  as  may  happen  any 
year  in  some  localities. 

THE  SPOTTED  ROOT  FLY. 

(Enxesta  not  at  a Wied.) 

This  pretty  little  fly  of  omnivorous  habits  was  reared  from  Astra- 
galus viollissimus  from  Hugo,  Colo.,  in  June  and  July,  1905,  being 
associated  with  the  fickle  midge  and  the  loco  root-maggot.  In  its 


INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS. 


39 


larval  stage  it  displays  a remarkable  diversity  of  habits,  although  it 
is  evidently  by  choice  a root  feeder  and  is  also,  with  the  seed-corn 
maggot  and  many  related  insects,  a scavenger  by  nature,  following  in 
some  cases  original  attack  by  some  other  form  of  insect.  It  has  been 
recorded  by  Dr.  L.  O.  Howard  as  having  been  bred  from  larvae  in 
human  excrement  in  houses  and  out  of  doors.  Mr.  E.  G.  Titus  has 
reared  it  from  sugar  beet  collected  at  Olney,  Colo.,  and  from  cockle- 
bur  collected  at  St.  Matthews,  S.  C.,  where  it  was  feeding  in  the  cells 
of  a weevil,  Baris  transversa.  In  September,  1905,  it  was  reared  by 
the  writer  from  onions  infested  by  Tritoxa  fiexa  from  Williamson 
School,  Pa.,  and  there  is  positive  evidence  that  it  had  fed  on  the 
onion  bulbs,  as  neither  stems  nor  leaves  were  present.  Dr.  J.  B. 
Smith  also  has  reared  it  from  onions.  In  1906  it  was  reared  from 
corn  on  the  farm  of  Dr.  B.  T.  Galloway  near  the  District  of  Colum- 
bia, where  it  was  reported  injurious,  the  injury  being  at  first  attrib- 


Fig.  12. — Spotted  root  fly  ( Euxesta  notata ) : Adult  male  at  right;  female  at  left. 
Much  enlarged  (original). 

uted  to  the  seed-corn  maggot,  as  attack  was  to  seed  corn  and  resem- 
bled the  work  of  the  latter  species.  From  cabbage  it  has  been  reared 
on  two  occasions,  viz,  from  the  roots  collected  at  Washington,  D. 
C.,  and  from  maggot-infested  roots  received  from  Bethel,  Alaska. 
It  has  also  been  bred  from  the  pulp  of  Osage  orange,  from  apples  in- 
fested by  the  codling  moth,  from  sumach  fruit,  from  the  bolls  of 
cotton,  and  from  Solanum.  It  is  not  rare  in  diseased  cotton  bolls. 

This  fly  belongs  to  the  same  family  as  the  preceding,  the  Ortali- 
dae,  and  is  shown  in  figure  12,  where  it  will  be  seen  that  it  has  a large 
head  and  flat  body.  Each  wing  is  marked  with  two  black  spots. 
The  female  is  distinguished  from  the  male  by  its  more  slender  form, 
smaller  head,  and  pointed  abdomen,  which  bears  near  the  anal  ex- 
tremity a distinct  white  transverse  band.  The  body  is  metallic  blue. 

Our  rearings  show  that  larvae  have  come  under  observation  from 
May  27  to  as  late  as  October  2 and  that  flies  have  issued  from  various 
sources  June  10-July  30,  September  8-21,  and  throughout  October. 


40 


MISCELLANEOUS  RESULTS  OF  WORK  OF  B BUREAU— IX. 


THE  BUR-CLOVER  APHIS. 

( Aphis  medicaginis  Ivocli.) 

This  species  is  well  known  to  attack  both  Astragalus  and  Aragallus, 
as  well  as  various  other  related  plants,  including  clover,  cowpea, 
alfalfa,  coffee  bean  (Cassia),  bur-clover,  Caragana  arborescens , 
Robinia  viscosa , Melilotus  itcdica , and  GlycymRiza  lepidota.  It  has 
also  been  observed  on  oxalis,  and  on  cotton  associated  with  the 
common  and  more  destructive  cotton  or  melon  aphis. 

Certain  of  our  correspondents  have  remarked  on  the  occurrence 
of  ladybirds  and  ants  on  infested  loco  plants,  conclusive  evidence 
in  the  case  of  the  ladybirds,  Hippodamia  convergens  Guer.,  that 
aphides  were  present. 

The  present  species  has  a considerable  literature,  having  been  de- 
scribed in  1857  and  afterwards  treated  more  or  less  fully  by  Monell, 
Thomas,  Oestlund,  Cowen,  Osborn,  Hunter,®  and  Sanderson. 

A somewhat  complete  account  of  this  aphis  was  given  by  Sanderson 
in  1906, ^ including  a consideration  of  its  food  plants  and  descriptions 
of  different  stages  as  well  as  references  to  literature.  Still  other 
bibliographical  references  have  been  given  by  Hunter.®  This  species 
is  evidently  of  foreign  origin  and  was  first  noticed  in  this  country  at 
St.  Louis,  Mo.,  by  Monell  in  1879. 


THE  MEAL  SNOUT-MOTH. 

( Pyralis  farinalis  L.) 

During  July,  1907,  a colony  of  the  larva  of  this  beautiful  pyralid 
moth  was  observed  by  the  writer  breeding  in  the  roots  of  Astragalus 
molUssimus  received  from  Hugo,  Colo.  Since  the  species  is  of  cosmo- 
politan distribution  and  commonly 
found  in  most  barns,  storehouses,  and 
even  in  dwellings,  it  can  not  be  posi- 
tively stated  that  it  attacks  loco  roots 
in  the  open,  but  it  quite  likely  infests 
the  dead  roots.  Frequently  this  spe- 
cies breeds  in  clover  hay,  after  the 
manner  of  the  clover-hay  worm,®  to 
which  it  is  related.  As  a rule  the 
larva  requires  for  its  development  a 
certain  amount  of  moisture,  feeding 
on  dry  material  which  has  become 
heated,  as  in  the  case  of  stored  grain  or  stacked  hay.  This  species  is 
shown  natural  size,  the  moth  at  a and  the  larva  at  b of  figure  13. 
More  complete  accounts  of  the  meal  snout-moth  are  given  elsewhere.'* 


nalis):  a,  Moth;  b , larva;  c,  chrysalis, 
natural  size;  d,  head  of  larva;  e , anal 
segment  of  larva;  /,  tip  of  pupa.  En- 
larged (author’s  illustration). 


0 Bill.  60,  Iowa  Agr.  Exp.  Sta.,  The  Aphididee  of  North  America,  1001,  p.  101. 
h Bui.  57,  Bur.  Ent.,  U.  S.  Dept.  Agr.,  pp.  26-29. 
r H ypsopggia  ( Axop'ia ) costalis  Fab. 

d See  Yearbook  U.  s.  Department  of  Agriculture  for  1S94,  p.  286,  and  Farmers’ 
Bulletin  45,  pp.  10,  11. 


INSECTS  INJURIOUS  TO  THE  LOCO  WEEDS. 


41 


PLANT-BUGS,  LEAFHOPPERS,  ETC. 

Numerous  plant-bugs,  leafhoppers,  and  related  insects  were  ob- 
served and  collected  at  Hugo,  Colo..  As  a considerable  portion  of 
these  were  in  the  nymph  or  immature  stages,  comparatively  few 
were  identified  specifically.  The  list  follows : 

Alydns  eurinus  Say  and  A.  pluto  Uhl.,  coreid  plant-bugs  bearing  some  relation 
to  the  squash  bug,  were  among  the  number.  The  former  ha,s  been  recorded 
attaqjdng  Lima  beans  and  cowpeas;  hence,  it  is  quite  probable  that  both  feed 
on  loco  and  lupines,  which  are  of  the  same  botanical  family. 

Dasycoris  humilis  Uhl.,  another  coreid  of  unknown  habits. 

Gcocoris  grlseus  Dali.,  a plant-bug  of  the  family  Lygseidse. 

Hadronema  militaris  Uhl.,  a small  capsid  or  leaf-bug.  It  infests  Amaranthus 
and  beets.  Probably  accidental. 

Stiphrosoma  atrata  Uhl.,  also  a capsid,  of  unknown  habits. 

Philcmus  bilineatus  Say,  a cercopid  leafhopper  which  probably  feeds  on 
grasses. 

Deltocephalus  flexulosus  Ball,  a jassid  leafhopper. 

Bruchomorplia  dorsata  Fitch,  a fulgorid. 

JVabis  ferus  L.,  a predatory  form.  It  doubtless  destroys  many  of  the  other 
bugs,  especially  in  their  immature  stages. 

MISCELLANEOUS  INSECTS. 

Agromyza  ceneiventris  Fallen,  a small  fly,  was  reared  from  pupae  at  the 
roots  of  Aragallus  from  Flagstaff,  Ariz.,  received  in  April,  1007,  from  Mr.  Geo. 
Ilochderffer.  We  have  office  records  of  the  rearing  of  this  species  from  the 
roots  of  clover  and  from  larvae  found  in  burrows 
in  the  stems  of  Ambrosia.  The  fly  was  reared 
by  the  writer  from  mines  in  garden  peas  col- 
lected at  Washington,  D.  C.,  August  10,  1904. 

The  insects  issued  July  30.  Pea  leaves  are,  in 
fact,  quite  often  infested  by  this  miner. 

Unknown  leaf -beetle. — December  14,  1901, 

Mr.  D.  P.  Marum,  Woodward,  Okla.,  wrote  of 
an  insect  which  fed  upon  the  leaves  of  Astra- 
galus mollissimus.  During  April  of  that  year 
he  noticed  that  a few  stems  in  each  hill  of  loco 
were  stripped  of  leaves,  and  found  on  the  plants 
a small  beetle  which  he  believed  to  be  a lady- 
bird, although  it  did  not  have  the  bright  spots 
known  to  be  present  on  Coccinellidae  inhabiting 
that  region. 

Bruchus  obsoletus  Say  (fig.  14)  was  stated  by  its  describe!*  to  have  been 
found  on  a species  of  Astragalus,  but  recent  researches  show  that  the  plant  in 
question  was  a related  one,  the  goats’  rue,  Cracca  ( Tephrosia ) virginicaA 

Bruchus  aureolus  Horn. — Recorded  as  occurring  on  the  flowers  of  Astragalus 
in  Owens  Valley,  Cal.  (Insect  Life,  Vol.  V.,  pp.  166,  167). 

Unknown  hymenopterous  gall. — Among  other  material  collected  at  Hugo, 
Colo.,  were  stems  of  Aragallus  lamberti  containing  elongated  fusiform  galls 
one-half  to  one  inch  in  length  and  about  one-third  that  in  width.  Each  of  these 
contained  a single  large  hymenopterous  larva  : these,  however,  were  not  reared. 

a An  illustration  of  this  insect  and  its  food  plant  were  furnished  in  the 
Annual  Report  of  the  Department  of  Agriculture  for  1892,  p.  172,  PI.  VII. 


Fig.  14. — Bruchus  obsoletus : a,  Beetle: 
b,  antenna;  c,  prothorax,  a,  c,  Much 
enlarged;  6,  more  enlarged.  (From 
Riley.) 


42 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Rusticus  ( Lyccena ) acmon  Doubl.  & Hew.  This  very  pretty  blue  butterfly 
was  reared  from  Astragalus  mollis simus  from  Hugo,  Colo.,  the  adult  issuing 
July  20,  1906.  Nothing  has  been  published  in  regard  to  the  natural  habits  of 
this  species,  and  it  is  not  known  if  it  plays  any  important  part  in  the  reduction 
of  the  loco  weeds. 

Grasshoppers  and  related  insects  were  collected  in  some  numbers  at  Hugo, 
Colo.,  on  Aragailus  lambcrti.  They  were  mostly  in  the  nymph  condition  and 
therefore  could  not  be  readily  identified.  There  were  two  species  of  grasshop- 
pers ( Melanoplus  spp.),  each  occurring  in  about  equal  numbers,  and  a smaller 
grasshopper  ( Opeia  obscura  Scudd.),  a walking  stick  ( Parabacillus  coloradus 
Scudd.)  and  a tree-cricket  ( CEcanthus  sp.).  Probably  none  of  these  accom- 
plishes much  in  the  line  of  defoliation  of  the  loco  with  the  exception  of  the  two 
Melanopli,  which  are  allied  to  the  pernicious  Rocky  mountain  locust. 

Aphioehceta  pygmcca  Zett. — This  small  fly,  which  belongs  to  the  Phoridse,  was 
reared  from  Astragalus  mollissimus,  from  Hugo,  Colo..  July,  1906,  from  roots  in 
which  other  species  wrere  breeding.  This  is  a European  species  known  from 
Texas  westward  to  California. 

In  the  compilation  of  the  above  list  the  writer  is  indebted  to  Mr. 
D.  W.  Coquillett  for  assistance  in  identifying  some  of  the  Diptera 
mentioned,  to  Mr.  Otto  Heidemann  for  the  identifications  of  the 
plant-bugs,  leaf  hoppers,  etc.,  and  to  Mr.  A.  N.  Caudell  for  naming 
the  grasshoppers  and  related  insects. 


O 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  VI. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  GREENHOUSE  THRIPS 


BY 


IT.  M.  RUSSELL, 


Agent  and  Expert. 


Issued  August  4,  1909. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 


1909. 


CONTENTS. 


Page. 

Introduction 43 

History 43 

Recent  records < 44 

Nature  and  extent  of  injuries 44 

Origin  and  distribution 45 

Description 46 

The  adult 46 

The  egg 47 

The  larva,  first  stage 47 

The  larva,  second  stage.. 47 

The  young  nymph  or  prepupa 47 

The  full-grown  nymph  or  pupa 48 

Habits  of  the  adult 48 

Habits  of  the  larvae 49 

Habits  of  the  prepupa  and  pupa 50 

Food  plants 51 

Life  history 51 

Life  cycle 51 

Longevity 51 

Generations 52 

Natural  control * 52 

Rain 52 

Natural  enemies 52 

Artificial  control 52 

Experiments  with  remedies 52 

Fumigation  experiments : 52 

Spraying  experiments 56 

Summary  of  experiments 57 

Remedies  recommended 57 

Bibliography 58 


ILLUSTRATIONS. 


Page. 

Fig.  15.  Greenhouse  thrlps  ( Heliothrips  haemorrhoidalis) : Adult  female  and 

antenna 46 

16.  Greenhouse  thrips:  Egg,  first-stage  larva,  full-grown  larva 47 

17.  Greenhouse  thrips:  Prepupa,  pupa 48 


ii 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  VI. 


Issued  August  4,  1909. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OE  THE  BUREAU  OE  ENTOMOLOGY— IX. 


THE  GREENHOUSE  THKIPS. 

By  H.  M.  Russell, 

Agent  and  Expert. 

INTRODUCTION. 

This  insect  has  been  known  since  1833  to  have  been  the  cause  of 
much  injury  to  greenhouse  plants;  but  its  life  history  has  never  been 
(fully  worked  out.®  The  writer,  while  engaged  in  field  work  in  the 
State  of  Florida  during  1907,  had  his  attention  called  to  a “ diseased” 
condition  of  crotons  in  one  of  the  greenhouses  at  Orlando.  This 
condition  was  found  to  be  caused  by  the  extreme  abundance  of  a spe- 
cies of  thrips  feeding  on  the  foliage.  Specimens  of  the  adult  were 
i sent  to  Dr.  W.  E.  Hinds,  who  determined  them  to  be  Heliothrips 
\hsemorrhoidalis  Bouche.  While  working  under  the  direction  of 
Dr.  F.  II.  Chittenden  during  the  winter  of  1907-8,  the  writer  made  a 
i study  of  this  insect’s  life  history  and  the  means  by  which  it  might  be 
controlled. 

HISTORY. 

The  species  was  first  described  by  Bouche,1  in  1833,  as  Thrips 
hxmorrhoidalis  from  specimens  taken  in  a greenhouse  in  Europe.  At 
that  time  he  wrote  that  he  believed  the  native  land  of  the  species  to 
be  America.  That  this  supposition  was  correct  appears  evident  at 
the  present  time. 

Packard,10  writing  in  1870,  described  this  species  for  the  first  time 
from  this  country.  He  wrote:  “This  is  one  of  the  greatest  pests  in 
Dur  hothouses.  It  is  the  Heliothrips  hxmorrhoidalis  of  Burmeister.” 
Packard  called  it  the  greenhouse  thrips  and  gave  a meager  descrip- 
tion of  the  larva  and  adult,  and  an  illustration  of  the  latter,  but 
j neither  descriptions  nor  drawing  are  exact  enough  to  identify  speci- 
3 mens.  He  furnished  a list  of  food  plants,  a description  of  injury, 
md  recommended  washing  plants  with  soapsuds  as  a remedy. 

aThe  external  and  internal  anatomy  of  this  insect  has  been  fully  worked  out  by 
several  European  entomologists,  while  others  have  made  incomplete  studies  of  the 
ife  history  on  the  Continent. 


43 


44 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU  IX. 


Under  the  name  Thrips  adonidum , A.  J.  Cook,11  writing  of  this  spe- 
cies, in  1874,  said:  “ Around  Detroit,  here  at  Adrian,  and  m our  south- 
ern counties  they  are  likewise  a serious  pest. 

In  1882  Mr.  Th.  Pergande13  recorded  this  insect  as  taken  out  ot 
doors  at  Washington,  D.  C.,  on  apple  late  in  November  J.  A.  Lint- 
ner  15  in  1885,  on  this  authority,  lists  it  as  an  insect  affecting  the  apple 
Nothing  more  was  written  about  this  species  in  this  country  until 
1896  when  G.  C.  Davis21  wrote  of  “ a black  species,  Heliothnps  Tisemor- 
rhoidalis,  which  we  have  found  most  common  on  croton  plants.  As 
far  as  noticed  its  work  is  confined  to  the  underside  of  the  leaves 
where  the  spots  are  eaten,  so  that  the  work  clearly  resembles  that  ot 

the  red  spider.”  , . . . 

Dr.  F.  H.  Chittenden,24  in  1902,  predicted  that  this  species,  which 

he  called  the  “ greenhouse  thrips,”  would  probably  increase  m num- 
bers and  destructiveness  with  time. 

Hinds25  wrote  of  this  insect  the  same  year:  “It  has  been  very  inju- 
rious in  some  places.”  He  also  added  that  it  was  called  the  black 
fly”  in  Germany  and  that  its  life  history  was  unknown. 


recent  records. 


This  species,  determined  by  Mr.  Pergande,  was  sent  in 
Bureau  of  Entomology,  January  8,  1908,  by  Mr.  P.  J.  Wester,  o 
Miami  Fla. , who  collected  it  on  mango  ( Mangifera  indica) . He  w ro  e . 
“It  has  never  appeared  to  do  serious  damage  unti  - t is  year,  j 
Mr.  I.  J.  Condit,  a collaborator  of  this  bureau,  at  San  Luis  Obispo, 
Cal  reported  it  injurious  in  a greenhouse  at  that  place  in  September,! 
1908,  and  again  reported  it  on  November  2,  1908,  as  injurious  to  orna-i 
mentals  in  one  of  the  parks  at  Santa  Barbara,  Cal. 

NATURE  AND  EXTENT  OF'INJURY. 

The  damage  caused  by  the  greenhouse  thrips  is  confined  to  tliJ 
foliage  of  ornamental  plants  entirely,  in  so  far  as  the  author  is  aware! 
for  he  knows  of  no  recorded  injury  to  the  blossoms  of  p ants  nor  haj 
he  noticed  any.  Injury  effected  by  the  thrips  is  due  to  the  method  ol 
feeding  on  the  plants.  Adults  and  larv*  both  obtain  their  food  bjl 
puncturing  the  epidermis  of  the  leaf  with  their  sharp  mouth-parts  I 
and  after  lacerating  the  tissue  they  suck  out  tissue  and  plant  juic  1 
at  the  point  of  attack.  The  insects  then  attack  the  leaf  in  a nej 
place,  so  that  in  time  it  becomes  full  of  tiny,  pale-colored  spots  wliertf 

the  tissue  and  chlorophyll  have  been  extracted.  j 

In  the  case  of  croton  plants,  upon  which  this  insect  was  studied 
injury  was  noticed  first  on  the  older  leaves  and  gradually,  as  thesl 
became  badly  infested,  the  injury  spread  until  the  young  leaves  wer 


a For  structure  of  mouth-parts  see  “The  Pear  rhrips. 
Part  I,  Bur.  Ent.,  U.  S.  Dept.  Agr.,  pp.  2-3,  1907. 


by  Dudley  Moulton,  Bui.  6*1 


THE  GREENHOUSE  THRIPS. 


45 


attacked,  soon  after  unfolding.  The  infested  leaves  first  showed 
injury  on  the  underside,  where  the  surface  appeared  full  of  minute 
white  spots.  As  attack  continued,  these  spots  became  more  numer- 
ous and  united,  forming  blotches  where  the  leaf  was  devoid  of  tissue. 
The  injury  then  became  apparent  from  the  upper  side,  as  the  surface 
developed  a twisted  and  distorted  aspect  between  the  lateral  veins,  ' 
and  was  finally  evidenced  by  wilted  and  dead  areas  around  the  edges 
of  the  leaf.  In  severe  attacks  the  insects  spread  to  the  upper  sur- 
face of  the  leaves,  and  in  a short  time  this  as  well  as  the  underside  is 
nearly  devoid  of  color.  Both  surfaces  become  thickly  covered  with 
minute  drops  of  reddish  fluid  voided  by  the  thrips,  which  gradually 
change  to  black.  As  the  attack  continues,  the  leaves  become  limp  and 
yellow  and  eventually  drop  off,  so  that  plants  that  were  not  treated 
to  prevent  injury  in  many  cases  lost  their  entire  foliage.  The  injury 
is  similar  on  other  ornamentals. 

This  insect  injures  plants  in  two  ways:  First,  it  causes  a serious 
drain  on  the  vitality  of  the  plant  from  the  feeding  of  thousands  of 
thrips,  so  that  the  growth  is  seriously  checked  and  in  neglected  cases 
would  cause  the  death  of  the  plant.  Secondly,  it  destroys  the  beauty 
of  the  plants  for  ornament  by  despoiling  them  of  their  foliage. 

ORIGIN  AND  DISTRIBUTION. 

Although  this  insect  was  first  described  from  Europe  and  is  there 
widely  distributed,  it  is  without  doubt  indigenous  to  tropical  America. 
Pergande19  writes  that  this  insect  was  1 1 probably  introduced  with 
ornamental  plants  from  the  warmer  regions  of  America and  that  it 
“is  found  upon  wild  and  cultivated  plants  in  Brazil.”  Franklin27 
records  it  in  Barbados  as  follows:  “This  species  is  found  in  the  open 
in  St.  Vincent  and  Barbados.  It  is  evidently  a tropical  species.” 
This  insect  has  been  collected  at  Miami,  Fla.,  on  plants  growing  in  the 
open  in  midwinter.  Moulton26  says,  “out  of  doors  it  feeds  and  be- 
comes very  destructive  to  Laurestinas.”  Mr.  Condit,  writing  of  this 
species  from  Santa  Barbara,  Cal.,  November  2,  1908,  said  that  it  was 
doing  considerable  damage  to  ornamentals  in  one  of  the  parks. 

These  records  of  occurrences  at  several  localities  in  the  Tropical  and 
Lower  Austral  life  zones  of  this  country  point  strongly  to  tropical 
America  as  its. original  home.  This  is  further  strengthened  because 
of  its  well-known  habit  of  living  in  greenhouses,  in  many  localities, 
upon  exotic  plants  from  the  Tropics.  From  this  habit  it  has  become 
widely  distributed  in  Europe  and  North  America.  In  Europe,  Walker 
and  Cameron  record  it  from  several  places  in  England,  Bouche  and 
others  from  Germany,  Ileeger  and  Low  from  Vienna,  and  Reuter 
from  Finlan’d.  It  has  also  been  recorded  from  France  and  Italy. 

In  this  country  it  has  been  recorded  from  Massachusetts,  from 
several  places  in  Michigan,  and  from  Washington,  D.  C.,  Florida,  and 


46 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU- — IX. 


California.  It  has  been  collected  in  Iowa  and  Pennsylvania  and 
recently  in  the  Barbados  and  the  island  of  St.  Vincent. 

Because  of  the  fact  that  it  has  been  collected  in  such  widely  dis- 
tant places  in  all  sections  of  the  country,  we  can  safely  say  that  Heli- 
othrips JisemorrJioidalis  is  generally  distributed  in  greenhouses  through- 
' out  the  United  States. 

DESCRIPTION. 


Heliothrips  hsemorrhoidalis  belongs  to  the  family  Thripidae,  the 
genus  being  characterized  by  having  antennae  with  8 segments  and 
the  body  with  a markedly  reticulated  surface.  This  is  especially 


Fig.  l').— Greenhouse  thrips  ( Heliothrips  hxmorrhoidalis ):  Adult  female,  enlarged  about  50  diameters 
and  greatly  enlarged  drawing  of  antenna  underneath.  (Original.) 


pronounced  on  the  head  and  thorax.  The  legs  are  unarmed  anc 
the  wings  are  characterized  by  having  the  fore-wings  broad  at  the 
base,  with  2 longitudinal  veins. 

The  adult  (fig.  15). — When  the  adult  first  emerges  the  abdomen  |j 
pale  yellow,  with  the  head  and  thorax  darker,  and  the  antennae,  legsij 
and  wings  appearing  white.  In  the  course  of  several  hours,  however; 
the  insect  becomes  fully  colored.  The  head  and  thorax  are  theij 
dark  brown,  the  abdomen  yellowish  brown,  fading  at  the  apex  t< 
brownish-yellow.  In  the  female  the  antennae  are  twice  as  long  a 


THE  GREENHOUSE  THRIPS.  47 

the  head.  The  total  length  is  about  1.25  mm.  and  the  greatest 
width,  across  the  mesothorax,  is  about  0.30  mm.° 

The  male  has  not  been  described,  and  this  species  is  without  ques- 
tion parthenogenetic  for  many  generations. 

The  egg. — The  egg  (fig.  16,  a)  is  bean-shaped,  0.296  mm.  in  length 
and  0.088  mm.  in  width,  very  delicate,  with  a thin  shell,  and  color- 
less. Eggs  are  laid  in  the  leaf  tissue  of  the  host  plant,  generally  on 
the  underside. 

The  larva , first  stage  (fig.  16,  h). — [Description  made  while  larva  was  very  young  and 
before  it  had  commenced  to  feed  on  the  plant.]  Length,  0.  31  mm.;  width  of  meso- 
thorax, 0.10  mm.  General  shape  fusiform;  antennae,  head,  and  legs  very  large  in  pro- 
portion to  the  rest  of  the  body.  Color  translucent  white.  Head  large,  quadrate;  eyes 
reddish,  ocelli  absent.  Antennae  0.16  mm.  in  length;  7-segmented;  b basal  segment 
cylindrical,  short,  with  spine  on  inner  side;  second 
segment  twice  as  long  as  basal  one  and  not  as  wide, 
with  4 or  5 spines;  third  pedunculate,  ringed,  as 
long  as  segments  1 and  2 combined,  2 long  spines 
near  tip  of  segment;  fourth  pedunculate,  nearly 
twice  as  long  as  third,  tip  more  slender  than  third, 
ringed,  a number  of  prominent  spines  near  tip; 
fifth,  sixth,  and  seventh  slender,  equal  in  length, 
and  together  equaling  the  length  of  the  fourth,  each 
with  one  or  two  small  spines  near  the  tip.  Legs 
translucent  white,  long.  Abdomen  tapering  pos- 
teriorly; with  10  segments,  the  first  8 nearly  equal 
in  length,  ninth  and  tenth  somewhat  longer  than 
others.  Each  abdominal  segment  with  longitudi- 
nal rows  of  setae,  the  ninth  with  2 and  tenth  with 
4 spines  that  are  three  or  four  times  the  length  of 
the  setae. 

The  larva,  second  stage. — Length,  0.90  to  0.97  mm. ; 
width  of  mesothorax,  0.22  to  0.23  mm. ; shape  about 
same  as  in  first  stage;  body  long,  cylindrical,  sides 
nearly  parallel  until  fifth  abdominal  segment,  where  they  begin  to  taper  to  blunt  point. 
Color  of  thorax  and  abdomen  slightly  yellowish,  last  two  segments  of  abdomen  trans- 
lucent white;  alimentary  tract  plainly  indicated  by  the  brownish  color  given  to  it  by 
inclosed  food ; this  extends  from  the  metathorax  to  the  sixth  abdominal  segment.  Sur- 
face of  the  body  covered  with  minute  granulations.  Head  quadrate,  but  with  notch 
behind  the  eyes  on  each  side;  eyes  reddish,  ocelli  absent.  Antennae  7-segmented,  third 
and  fourth  distinctly  spindle-shaped  and  annulated,  fifth  and  sixth  slightly  annulated, 
and  together  with  seventh  segment  quite  slender.  Legs  translucent  white.  Abdo- 
men 0.50  mm.  in  length,  fusiform,  ovipositor  not  formed;  segments  with  rows  of  fine 
setae,  similar  to  those  in  adult,  increasing  in  length  toward  posterior  end,  ninth  and 
tenth  segments  equal  in  length  (0.059  mm.). 

The  young  nymph  or  prepupa  (fig.  17,  at  left). — Length,  1.184  mm.;  width  of  meso- 
thorax, 0.3404  mm.  Shape  similar  to  adult.  Head,  length,  0.148  mm. ; width  at  eyes, 
0.1628  mm.  Head  translucent  white,  vertex  slightly  yellowish,  ocelli  absent,  head 

aFor  a full  characterization  of  the  genus  and  of  the  species  see  Hinds’s  Monograph 
of  the  Thysanoptera,  pp.  168-170. 

6 After  careful  search  the  writer  has  been  able  to  make  out  what  he  considers  7 seg- 
ments in  the  antennae. 


Fig.  16.— Greenhouse  thrips:  a,  Egg; 
b,  larva,  first  stage;  c,  larva,  full 
grown.  All  enlarged  about  40  diam- 
eters. (Original.) 


48 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


deeply  notched  behind  eyes;  eyes  red,  made  up  of  a few  large  facets,  surface  faintly 
reticulated ; head  rounded  in  front;  a pair  of  setae  over  rear  angle  of  eyes,  another  pair  in 
front  of  the  eyes,  and  a third  over  the  antennae.  Antennae  translucent,  extending 
forward  about  twice  the  length  of  the  head  and  composed  of  7 segments;  first  seginent 
cylindrical,  broader  than  long;  second  cylindrical,  nearly  twice  as  long  as  segment  1 
and  not  so  broad;  third  longer  than  second,  base  constricted  but  not  pedunculate,  and 
with  constriction  at  third  and  two-thirds  length  from  base,  so  that  it  appears  to  be  made 
up  of  3 segments;  fourth  spindle-shaped,  about  as  long  as  third;  5,  6,  and  7 short  and 
slender  and  not  very  clearly  defined.  Segments  bear  few  spines  on  sides. 

Prothorax  nearly  one-half  again  as  wide  as  long,  sides  rounded,  posterior  edge  broad- 
est, semitranslucent  white  to  faint  yellow,  a few  prominent  setae  around  edges.  Meso- 
thorax  with  prominent  rounded  angles,  translucent  white  to  faint  yellow,  surface 
faintly  reticulated,  wing-cases  translucent  white,  distinct  from  each  other,  those  of 
fore- wings  extending  to  second  abdominal  segment  and  those  of  hind- wings  extending 
to  middle  of  second  abdominal  segment.  Legs  translucent  white  to  faint  yellow,  strong. 
Abdomen  shaped  as  in  adult,  white  to  faint  yellow,  last  few  segments  translucent,  eight 

rows  of  setae  in  pairs,  increasing  in  length 
from  anterior  to  posterior  end.  Length  of 
abdomen,  0.5956  mm. 

The  full-grown  nymph  or  pupa  (fig.  17,  at 
right) . — Length,  1.25  mm. ; width  at  meso- 
thoracic  angles,  0.2812  mm.  Shape  similar 
to  that  of  adult.  Color  translucent  white 
to  slightly  yellowish.  Head,  length,  0.1628 
mm.;  width,  0.1924  mm.;  translucent 
white,  distinctly  reticulated,  eyes  dark  red, 
larger  than  in  prepupal  stage,  facets  large. 
Three  ocelli  present  in  close  triangle  be- 
tween eyes,  color  chitinous  yellow.  An- 
tennae laid  backward  on  head  and  reach- 
ing to  near  middle  of  prothorax,  segments 
indistinct,  translucent  white.  Segments 

1 and  2 projecting  in  front  of  the  head  and 

2 with  a long  spine  extending  forward, 
0.1332  mm.  in  length.  Thorax  plainly 
reticulated,  translucent  white  to  faint  yel- 
low. Prothorax  more  than  twice  as  broad  as  long.  W ing  cases  0.4736  mm.  long, 
extending  to  near  middle  of  fifth  abdominal  segment,  translucent  white  to  faint 
yellow.  Length  from  head  to  end  of  wing-pads,  0.6512  mm.  Legs  translucent  white 
to  pearly  white.  Abdomen  broader  and  shorter  than  in  adult,  contracted,  but  of  same 
general  shape,  surface  plainly  reticulated,  setae  well  developed,  the  longest  ones  at 
posterior  end.  Length  of  abdomen,  0.6956  mm.;  width,  0.3552  mm.;  length  of 
posterior  setae,  0.0888  mm. 


Fig.  17.— Greenhouse  thrips:  Prepupa  on  the  left 
and  pupa  on  the  right.  Enlarged  about  40 
diameters.  (Original.) 


HABITS  OF  THE  ADULT. 

After  emerging  from  the  pupae,  the  mature  thrips  feed  on  the  under- 
side of  the  leaves  for  several  weeks.  They  are  not,  as  a rule,  as  abun- 
dant on  the  upper  surface.  One  plant,  on  which  there  were  about 
150  adults,  had  only  3 or  4 of  this  number  feeding  on  the  upper  sur- 
face of  the  foliage. 

Adults  walk  over  the  leaf  quite  rapidly,  and  if  disturbed  they  raise 
t Ik-  tip  of  the  abdomen  and  move  rapidly  away,  walking  in  any  direc- 
tion. In  a few  cases  they  have  been  observed  to  jump  when  dis- 


THE  GREENHOUSE  THRIPS. 


49 


turbed,  but  generally  they  simply  move  rapidly.  The  writer  has 
never  observed  adults  in  flight,  but  that  they  do  fly  is  certain,  as  he 
has  found  that  plants  free  from  thrips  and  at  a distance  from  infested 
plants  after  a time  will  become  infested  by  adults.  As  the  study  of 
the  life  history  of  this  species  was  carried  on  in  an  unheated  green- 
house with  low  temperature,  it  is  quite  possible  that  the  adults  were 
rendered  sluggish.  It  seems  strange  that  the  writer  has  not  observed 
their  flight,  for  in  studying  this  thrips  he  has  examined  a large  num- 
ber on  plants  and  has  purposely  disturbed  them  to  induce  flight. 
Adults  often  remain  motionless  for  long  periods,  and  in  such  cases  rest 
close  to  the  veins  of  the  leaf. 

The  eggs  are  laid  singty  in  the  tissues  of  the  leaf,  the  female  first 
making  an  incision  with  her  ovipositor  and  then  pushing  the  egg  into 
the  incision.  She  probably  lays  only  1 or  2 eggs  in  a day,  as  the  eggs 
are  large  and  the  ovaries  w ill  hold  only  a few7  matured  eggs  at  one  time. 
One  female  examined  had  6 eggs  partly  formed  in  her  ovaries  and  3 of 
these  were  quite  small.  As  the  leaves  become  exhausted  from  the 
feeding  of  larvae  and  adults,  the  latter  leave  them  and  oviposit  in 
fresh  young  leaves,  so  that  in  time  the  exhausted  leaves  are  deserted 
and  fall  off  and  gradually  the  remainder  of  the  plant  becomes  infested. 

HABITS  OF  THE  LARV/E. 

On  March  5 larvae  were  observed  hatching  from  the  eggs  about  10 
a.  m.  In  all  cases  w here  larvae  emerged  the  leaf  was  marked  by  a 
dark  spot  and  the  surface  w^as  slightly  swmllen. 

When  first  observed  the  head  of  the  larva  wTas  projecting  slightly 
out  of  a slit  in  the  leaf  epidermis,  probably  the  same  one  that  was 
made  in  depositing  the  egg,  and  the  light  red  eyes  w7ere  very  conspicu- 
ous. Little  by  little  the  body  is  wmrked  more  and  more  out  of  the 
opening,  and  as  it  projects  in  the  air,  working  vigorously  back  and  forth, 
writh  its  limbs  folded  against  the  body  and  invisible,  it  has  the  ap- 
pearance of  a minute  worm  in  motion.  When  all  but  the  tip  of  the 
abdomen  is  free  the  tiny  larva  remains  quiet  for  a very  short  time, 
then  one  by  one,  beginning  with  the  antennae,  but  the  legs  in  no  regu- 
lar order,  the  appendages  unfold.  The  larva  moves  them  around 
freely  for  a time  and  then,  bending  over,  grasps  the  leaf  surface  and 
commences  to  pull,  in  an  effort  to  free  the  end  of  the  abdomen.  After 
considerable  w7ork  the  larva  frees  itself  and  after  a short  rest  moves 
around  in  search  of  a place  to  feed.  Some  only  travel  a few  inches, 
others  travel  over  a considerable  portion  of  the  leaf  surface  before 
settling  down  to  feed.  The  time  required  for  the  larva  to  emerge 
varies  from  6 to  12  minutes. 

As  a rule  the  larvae  are  found  on  the  underside  of  the  leaves,  but 
vrhen  crowded,  as  in  severe  infestations,  they  attack  the  upper  surface. 

88328— Bui.  64,  pt.  6—09 2 


50 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU- — IX. 


While  they  will  feed  anywhere  on  the  leaf,  in  many  cases  they  will 
cluster  together  in  colonies  between  two  veins  of  the  leaf.  In  one  case 
observed  by  the  author  a number  of  larvae  hatched  from  eggs  on  one 
edge  of  the  leaf  and  the  next  day  were  all  feeding  together  on  the 
opposite  edge.  In  another  case  a colony  of  85  larvae  was  observed 
collected  in  a circle  between  two  veins  near  the  edge  of  the  leaf. 
Many  of  the  larvae  in  this  colony  were  moving  around,  but  would  not 
separate  from  the  colony. 

The  larvae  when  first  hatched  are  minute  and  colorless,  but  as  soon 
as  they  begin  feeding  the  alimentary  tract  becomes  plainly  marked 
from  the  dark  reddish  fluid  contained  in  it.  This  fluid  is  excreted 
and  collects  in  globules  on  the  tip  of  the  abdomen,  being  held  in  place 
by  the  terminal  setae.  The  tip  of  the  abdomen  is  elevated,  and  it 
is  an  interesting  sight  to  see  numbers  of  these  larvae  moving  over 
the  leaf  with  globules  of  red  liquid  suspended  in  the  air  on  the  tips 
of  the  abdomen.  When  disturbed  they  become  excited  and  move 
around  rapidly,  jerking  the  abdomen  from  side  to  side.  The  globule 
of  liquid  gradually  increases  in  size  until  it  is  too  large  to  carry,  and 
is  then  left  on  the  surface  of  the  leaf,  where  it  dries  as  a small  reddish 
spot. 

As  long  as  the  food  supply  in  the  leaf  is  fresh  and  abundant  these 
arvae  will  remain  on  it,  and  thus  the  number  becomes  very  large. 
One  leaf  was  found  with  about  250  larvae,  besides  a number  of  pupae 
and  adults.  If  disturbed,  or  if  the  leaf  is  beginning  to  wilt  and  lose 
its  vitalit}7-,  the  larvae  become  restless,  separate,  and  move  around 
over  the  leaf  in  search  of  fresh  food,  but  eventually  many  will  collect 
again  in  colonies.  They  feed  unprotected  on  the  leaf,  as  far  as  their 
own  efforts  are  concerned,  but  in  many  cases  they  secrete  themselves 
under  a slight  web  made  by  red  spiders  and  are  protected  by  it. 
Upon  leaves  exposed  in  part  to  sunlight  the  larvae  seek  that  part  of 
the  leaf  which  is  the  least  exposed.  They  molt  unprotected  in  the 
midst  of  the  feeding  colony.  These  larvae  are  delicate  little  crea- 
tures, and  if  for  any  reason  they  are  knocked  from  the  plant  most  of 
them  soon  die,  not  being  able  to  travel  far  in  returning  to  the  food 
plant. 

HABITS  OF  THE  PREPUPA  AND  PUPA. 

The  larvae  change  to  prepupae  in  the  midst  of  the  feeding  colon}r 
without  seeking  protected  quarters,  but  nearly  always  on  the  under- 
side of  the  leaf.  The  prepupae  move  around  a little  on  the  underside 
of  the  leaf  and  generally  are  clustered  in  groups  of  from  4 to  10  pre- 
pupae  and  pupae.  In  many  cases  they  are  under  the  web  of  red 
spiders,  but  if  no  red  spiders  have  been  on  the  plant  they  are  then 
unprotected. 


THE  GREENHOUSE  THRIPS. 


51 


The  pupae  are  associated  with  the  prepupse,  but  do  not  move  about 
unless  disturbed.  Not  only  are  the  prepupae  more  active  than  the 
pupae,  but  they  carry  the  antennae  in  front  of  the  head  and  frequently 
move  them,  while  the  pupae  have  the  antennae  laid  back  on  the  head 
and  motionless.  Neither  prepupae  nor  pupae  take  any  nourishment. 

FOOD  PLANTS." 

Heliothri'ps  haemorrhoidalis  feeds  on  a large  number  of  ornamental 
plants.  In  this  country  it  has  been  recorded  as  feeding  on  the  fol- 
lowing: • Liliaceous  plants,  azalia,  Pellea  Jiastata,  aspidium,  crotons, 
dahlias,  phlox,  verbena,  pink,  ferns,  vines,  cherry  laurel,  lauristina, 
palms,  ficus,  and  fuchsia. 

This  year  this  thrips  damaged  the  mango  ( Mangifera  indica)  at 
Miami,  Fla.,  and  was  recorded  27  from  St.  Vincent  and  the  Barbados 
Islands  on  cacao,  kola,  and  the  date  palm.  In  Europe  the  following 
list  includes  most  of  the  ornamentals  preyed  upon  by  this  thrips: 
iErides,  azalia,  begonia,  camarotes,  catleyia,  crinums,  dendrobuim, 
eucharis,  ficus,  grape,  lselia,  lefortia,  marcintacia,  pancratium,  pha- 
lenopsis,  and  viburnum. 

LIFE  HISTORY. 

In  order  to  study  the  life  history  of  this  insect,  solitary  females  were 
put  on  isolated  plants  that  were  previously  uninfested  and  carefully 
watched.  An  attempt  to  study  isolated  females,  in  small  vials  with 
bits  of  leaves,  failed  of  results  and  after  2 weeks  was  discontinued. 

Life  cycle. — The  life  cycle,  as  detailed,  is  probably  very  near  the 
maximum  length,  as  the  studies  were  conducted  with  the  temperature 
of  the  house  quite  low,  frequently  falling  to  50°  F.  at  night.  With  these 
conditions  the  length  of  the  egg  stage  is  about  8 days,  but  possibly  in 
a well-heated  greenhouse  this  would  be  cut  almost  in  half.  The  larvae 
molt  twice,  the  last  time  transforming  to  prepupae,  and  during  the 
cool  weather  require  from  16  to  20  days  to  obtain  full  growth.  The 
prepupal  period  is  of  short  duration,  occupying  only  from  10  to  15 
hours,  while  the  pupal  period  is  from  4 to  5 days.  This  gives  a total 
of  33  days  as  a maximum,  and  with  favorable  conditions  this  is 
probably  reduced  to  20  days  or  less. 

Longevity. — The  greenhouse  thrips,  for  such  a minute  insect,  has 
quite  an  extended  duration  of  life  and  evidently  feeds  on  the  leaves 
for  a number  of  days  before  starting  egg-deposition.  In  one  case  ob- 

a Since  the  above  was  submitted  for  publication  some  new  food  plants  for  this  species 
have  been  reported.  Dr.  E.  A.  Back  found  it  feeding  on  maples  at  Orlando,  Fla. , and 
on  alligator  pear  ( Persea  gratissima).  The  fact  that  this  insect  feeds  on  the  mango  and 
alligator  pear  serves  to  indicate  that  at  some  time  in  the  future  it  may  be  of  great  im- 
portance in  Florida,  as  both  are  valuable  fruits  in  that  State. 


52 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU— IX. 


served,  no  larvse  hatched  until  19  days  after  the  female  was  placed  on 
a plant.  This  insect  was  about  1 day  from  the  pupa  when  placed 
on  the  plant.  Another  female  was  observed  for  4 weeks,  when  she 
disappeared,  quite  probably  dying  of  old  age.  Probably  this  thrips 
lays  from  10  to  20  eggs  during  her  lifetime.  The  writer  observed  10 
larvae  on  1 plant  with  a single  adult,  and  possibly  some  were  killed  by 
mites,  etc. 

Generations. — In  greenhouses  this  insect  is  active  during  the  entire 
year,  so  that  the  number  of  generations  is  quite  large.  Taking  the 
maximum  life  cycle,  this  thrips  might  produce  as  many  as  12  genera- 
tions a year,  provided  that  the  species  breeds  continuously  and  con- 
ditions are  favorable  to  rapid  growth. 

NATURAL  CONTROL. 

Bain. — In  its  native  home  this  thrips  is  probably  kept  under  con- 
trol by  frequent  rains.  At  Miami,  Fla.,  where  hundreds  of  crotons 
are  planted  on  hotel  and  private  grounds,  the  author  could  find 
no  traces  of  injury  and  collected  only  1 adult.  Crotons  that  were 
badly  infested  by  this  insect,  kept  in  a greenhouse  at  Orlando,  Fla., 
during  the  winter  of  1907,  were  placed  outside  in  June  and  by  the  end 
of  the  summer  it  was  almost  impossible  to  find  specimens  of  the  thrips 
on  them.  In  times  of  drought  this  insect  may  increase  in  such  num- 
bers as  to  cause  serious  injury  where  it  occurs  in  the  open. 

Natural  enemies. — Frequently  a mite  is  found  on  plants  infested 
with  the  greenhouse  thrips.  On  a few  occasions  the  author  has  found 
thrips  with  one  of  these  mites  fastened  to  its  dorsum.  Specimens  of 
this  predaceous  enemy  were  determined  by  Mr.  Nathan  Banks  as 
Lsetaps  macropilis  Bks. 

ARTIFICIAL  CONTROL. 

EXPERIMENTS  WITH  REMEDIES. 

FUMIGATION  EXPERIMENTS. 

A series  of  fumigation  experiments  was  conducted  against  this 
insect  in  its  occurrence  on  croton  at  Orlando,  Fla.  All  were  made  in 
a small,  fairly  tight  room,  containing  660  cubic  feet. 

Experiment  No.  1. — April  27,  1908,  at  4 p.  m.,  a plant  was  fumi- 
gated all  night  with  one  sheet  of  nico  fume.  It  was  a cloudy,  cool 
day,  just  after  a rain,  and  a good  breeze  was  blowing.  On  opening 
the  room  at  8.15  a.  m.  there  was  quite  a pronounced  odor  of  nicotine. 

April  28,  the  paper  below  the  plant  was  covered  with  this  insect  in 
all  stages,  and  many  were  also  found  on  the  plant. 


THE  GREENHOUSE  THRIPS. 


53 


Result  of  the  fumigation,  counting  the  thrips  on  the  plant: 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

109 

30 

436 

575 

A live 

10 

26 

10 

46 

Ppr  cent  killed 

' 91.6 

53 

97.6 

92+ 

May  2,  the  plant  was  in  fine  condition  and  uninjured.  About  10 
live  adults  remained.  No  live  larvae  were  seen,  but  the  leaves  were 
covered  with  hundreds  of  dead  ones. 

Experiment  No.  2. — May  16,  at  5.45  p.  m.,  a plant  was  fumigated 
overnight  with  one-half  sheet  of  nico-fume  paper.  At  5.45  p.  m.  it 
was  dark  from  rain  clouds. 

May  17,  the  plant  was  uninjured.  Red  spiders  and  mealy  bugs 
were  alive.  Few  thrips  were  on  the  plant. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

2 

5 

10 

17 

Alive 

0 

13 

0 

13 

Per  cent  killed 

100 

27+ 

100 

56§ 

Experiment  No.  3. — April  28,  at  5.15  p.  m.,  fumigated  a plant  over- 
night with  one  sheet  of  aphicide.  The  sky  was  cloudy  and  there  was 
a strong  breeze.  The  plant  had  a few  thrips  on  it. 

April  29,  when  examined  at  8.45  a.  m.,  the  plant  was  uninjured. 


I 

Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

30 

1 

6 

37 

Alive 

3 

0 

2 

5 

Per  cent  killed 

90 

100 

75 

88+ 

May  2,  the  plant  was  in  fine  condition. 

Experiment  No.  4. — May  24,  at  7 p.  m.,  fumigated  a plant  with  one 
sheet-  of  aphicide.  There  was  a strong  breeze. 

May  25,  the  plant  was  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

3 

10 

67 

80 

Alive „ 

0 

2 

0 

2 

Per  cent  killed 

100 

83g 

100 

97+ 

54  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Experiment  No.  5. — May  22,  at  6 p.  m.,  fumigated  a plant  over- 
night with  one-half  sheet  of  aphicide.  There  was  a strong  breeze. 
May  23,  the  plant  was  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

6 

15 

31 

52 

Alive 

2 

21 

11 

34 

Per  cent  killed 

75 

41  § 

73.8 

60. 4+ 

Experiment  No.  6. — April  30,  at  8.30  a.  m.,  a plant  was  fumigated 
with  one  sheet  of  aphis  punk  ( = 2 sheets  of  nico  fume  or  aphicide)  all 
day;  cloudy.  Toward  the  end  of  the  fumigation  the  punk  began  to 
burn  in  strips,  so  it  was  not  all  consumed.  It  gave  a very  dense 
smoke.  The  room  was  opened  late  in  the  afternoon. 

May  1,  the  plants  were  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

7 

0 

3 

10 

Alive . 

14 

11 

18 

43 

Per  cent  killed 

33J 

0 

14.2 

18.8 

May  2,  live  thrips  were  abundant  on  the  plants. 

Experiment  No.  7 . — April  30,  fumigated  with  one-half  sheet  of  aphis 
punk  (equal  to  1 sheet  of  other  kinds),  but  as  it  did  not  burn  up,  the 
house  was  opened  at  5.30  p.  m.  and  a fresh  piece  put  in.  The  fumi- 
gation lasted  all  night.  This  piece  also  burned  in  strips  and  a third 
was  not  consumed. 

May  1,  the  plants  were  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

0 

2 

3 

5 

Alive 

11 

13 

15 

39 

Per  cent  killed 

0 

13£ 

16| 

11+ 

It  seems  that  the  thrips  that  drop  to  the  ground  have  a better 
chance  to  recover  than  those  on  the  plant. 

Experiment  No.  8. — May  1,  at  5.15  p.  m.,  fumigated  all  night  with 
one-half  sheet  of  aphis  punk  (fresh  box  from  the  factory) . This  was 
entirely  consumed  and  the  room  well  filled  with  smoke. 

May  2,  the  plants  were  uninjured;  red  spiders  were  alive. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

68 

1 

42 

Ill 

Alive.... 

4 

24 

1 

29 

Per  cent  killed 

94.4 

5 

97+ 

86.4 

THE  GREENHOUSE  THRIPS. 


55 


Experiment  No.  9. — May  26,  at  7 p.  m.,  fumigated  with  one-half 
sheet  of  aphis  punk  (fresh  box).  Fumigation  lasted  all  night.  The 
sky  was  cloudy. 

May  27,  the  plant  was  uninjured.  The  condition  of  the  thrips  was 
as  follows: 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

7 

2 

2 

11 

Alive 

0 

7 

0 

7 

Per  eent,  killed 

100 

22+ 

100 

61* 

Experiment  No.  10. — May  20,  at  5.50  p.  m.,  fumigated  with  nico- 
fume  liquid  (1  tablespoonful  = J ounce  + 1 ounce  water,  vaporized 
over  an  alcohol  lamp) . The  sky  was  partly  cloudy.  Sprinkled  the 
plant  with  water. 

The  vapor  rose  slowly  until  6 p.  m.,  when  small  flies  on  the  window 
began  to  drop.  House  flies  were  still  flying  around  the  room  at  6.15 
p.  m.,  when  the  liquid  was  all  evaporated. 

May  21,  the  plant  was  uninjured.  Red  spiders  were  apparently 
all  alive.  A very  careful  examination  of  the  plant  failed  to  show  a 
live  thrips. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

74 

12 

8 

94 

Alive 

0 

0 

0 

0 

Per  cent  killed 

100 

100 

100 

100 

Experiment  No.  11. — May  27,  at  3.50  p.  m.,  fumigated  with  nico- 
fume liquid  (|  tablespoonful  to  2 tablespoonfuls  of  water,  vaporized). 
Sky  clouded,  breeze  strong. 

May  28,  the  plant  was  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead ’ 

3 

2 

1 

6 

Alive 

0 

2 

0 

2 

Per  cent  killed 

100 

50 

100 

75 

Experiment  No.  12. — May  21,  at  6 p.  m.,  fumigated  with  rose-leaf 
insecticide  (29  c.  c.  + 25  c.  c.  water,  vaporized  over  an  alcohol  lamp). 
The  sky  was  cloudy,  with  rain  falling. 

May  22,  the  plants  were  apparently  uninjured.  Red  spiders  were 
alive. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

7 

2 

4 

13 

0 

0 

0 

0 

Per  cent  killed 

100 

100 

100 

100 

56 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Experiment  No.  13. — May  18,  fumigated  with  potassium  cyanid 
(0.00§  gram  per  cubic  foot.  In  660  cubic  feet  used  4.4  grams  potas- 
sium cyanid,  7.92  C;  c.  sulphuric  acid,  and  15  c.  c.  water).  Time,  5.30 
p.  m.  Sky  clouded;  temperature  82°  F;  breeze  strong;  length  of 
fumigation,  overnight. 

May  19,  the  plant  was  uninjured. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead 

8 

0 

1 

9 

Alive 

2 

17 

54 

73 

Per  cent  killed 

80~ 

0 

1.8 

10.9 

This  strength  was  entirely  too  weak. 

Experiment  No.  IJf. — May  19  fumigated  with  potassium  cyanid 
(0.02  gram  per  cubic  foot.  In  room  used  13.2  grams  potassium  cya- 
nid, 26.8  c.  c.  sulphuric  acid,  and  53.6  c.  c.  water).  Time,  6 p.  m. 
Length  of  fumigation,  all  night.  Temperature,  78°  F.;  breeze  strong. 

May  20,  the  plants  were  uninjured.  Flies  and  bees  in  the  room 
were  all  dead.  Red  spiders  were  alive.  The  thrips  were  all  dead. 


Adults. 

Pupae. 

Larvae. 

All  forms. 

3 

10 

28 

41 

Alive ’ 

0 

0 

0 

0 

Per  cent  killed 

100 

1 

100 

100 

100 

May  25,  the  plant  was  uninjured. 


SPRAYING  EXPERIMENTS. 

Experiment  No.  15. — February  25,  sprayed  very  thoroughly  with 
rose-leaf  insecticide  (1  part  to  48  parts  water)  a large  croton  infested 
with  this  thrips  in  all  stages.  Gave  the  upper  and  under  sides  a very 
thorough  spraying  so  as  to  cover  entirely  the  surface  and  be  sure  to  hit 
nearly  all  of  the  thrips.  The  spraying  was  done  in  the  afternoon 
when  the  house  became  shaded  from  the  sun.  A fine  spray  from  a 
small  hand  pump,  common  in  greenhouses,  was  used. 

February  26,  examined  the  plant  at  9.30  a.  m.  and  find  results  as 
follows : 


Adults. 

Pupae. 

Larvae. 

All  forms. 

Dead ...  ' 

34 

5 

5 

44 

Alive 

1 

2 

2 

5 

Per  cent  killed 

97.  1 

71.4 

71.4 

90 

May  12,  1908,  this  plant  had  then  a number  of  young  thrips  upon  it 
again  and  a lot  of  adults  that  bad  flown  onto  it. 


THE  GREENHOUSE  THRIPS. 


57 


Experiment  No.  16. — February  20 , 1908,  sprayed  with  cold  water. 
Took  hose  and  washed  off  all  of  the  plants  in  the  greenhouse  with  cold 
water.  The  next  morning  found  the  adults  still  common  and  also 
many  larva^  on  the  crotons,  but  many  leaves  badly  infested  before 
washing  were  then  entirely  free  from  them.  Probably  the  spraying 
with  cold  water  washed  away  and  killed  40  to  50  per  cent  of  young 
thrips. 

SUMMARY  OF  EXPERIMENTS. 

The  fumigation  and  spraying  experiments  in  the  control  of  the 
greenhouse  thrips  may  be  summarized  as  follows: 


No.  of 
experi- 
ment. 

Date. 

Method. 

Material. 

Amount  per  660 
cubic  feet. 

1 Per  cent 
killed. 

Injury  to 
plant. 

Status  of 
red  spider 
after  treat- 
ment. 

1 

Apr.  27 

Fumigation. . . 

Nico-fume  paper. 

1 sheet 

92 

None 

Alive. 

2 

May  16 

do 

do 

5 sheet 

56.  6 

...do 

Do. 

3 

Apr.  28 

do 

Aphicide 

1 sheet 

88 

1 . . .do 

Do. 

4 

May  24 

do 

do 

do 

97 

. . .do 

Do. 

5..  . 

May  22 

do 

do 

5 sheet . . 

60.  4 

.do 

Do. 

6. 

Apr.  30 

do 

Aphis  punk 

1 sheet . . 

18.  8 

.do 

Do. 

7 

. . .do 

do 

do 

\ sheet 

11  + 

. . .do 

Do. 

8 

May  1 

do 

do 

.I-.-do 

86.4 

...do 

Do. 

9. 

May  26 

.do 

.do . 

.do 

61+ 

.do 

Do. 

10 

May  20 

do 

Nieo-fume  liquid. 

\ ounce 

100 

...do 

Do. 

11 

May  27 

do 

.do . 

J ounce 

75 

do 

Do. 

12  . 

May  21 

do 

Rose-leaf  insecti- 

29 c.  c 

100 

do 

Do. 

cide. 

13 

May  18 

do 

Potassium  eya- 

0.00£  gram  per 

10.9 

...do 

Do. 

nid. 

cubic  foot. 

14 

May  19 

do 

do 

0.02  gram  per 

100 

. . .do 

Do. 

cubic  foot. 

15 

Feb.  25 

Spray..  . 

Rose-leaf  insecti- 

1  part  to  48  parts 

90 

. . .do 

Do. 

cide. 

water. 

16.  . 

Feb.  20 

do 

Water  in  hose 

Drenching 

40-50 

. . .do 

Do. 

REMEDIES  RECOMMENDED. 

For  the  treatment  of  this  pest  there  are  a number  of  good  remedies. 
The  question  as  to  the  best  method  to  employ  depends  upon  the  size 
of  the  house  infested  and  upon  the  experience  of  the  person  engaged 
in  treating  the  insect. 

Fumigation  with  nicotine  papers. — Any  of  the  standard  fumigating 
papers  will  give  good  results  against  this  pest  if  they  are  strictly  fresh 
and  kept  tightly  sealed.  Fumigation  should  be  done  at  night  in  a 
moist  atmosphere  and  the  papers  should  be  used  at  the  rate  of  about 
2 sheets  for  every  1,000  cubic  feet  of  space.  Early  in  the  morning 
the  house  should  be  opened  and  thoroughly  aired. 

Fumigation  with  nicotine  liquid  extracts. — Liquid  extracts  of  nico- 
tine offer  one  of  the  best  methods  of  greenhouse  fumigation  and  against 
this  pest  are  very  successful.  Those  made  up  of  40  per  cent  nicotine 
should  be  used  at  the  rate  of  1 ounce  to  every  1 ,000  cubic  feet  of  space 
and  the  weaker  solutions  at  greater  strengths.  The  preparation 
should  be  evaporated  over  small  lamps  or  stoves,  and  to  prevent 


58 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


scorching  should  be  diluted  with  water,  approximately  two-thirds. 
Fumigation  should  be  carried  on  at  night  in  a moist  atmosphere,  and 
the  house  should  remain  closed  all  night. 

Fumigation  with  hydrocyanic-acid  gas.a — When  fumigating  with 
hydrocyanic-acid  gas  great  care  should  be  taken,  as  this  gas  is  fatal  to  all 
animal  life.  The  work  must  be  conducted  at  night  and  the  plants 
should  have  dry  foliage.  In  treating  this  insect,  use  from  0.01  to  0.05 
grams  of  potassium  cyanid  per  cubic  foot  for  from  2 hours  to  all  night, 
the  strength  and  length  of  exposure  varying  according  to  the  tight- 
ness of  the  house  and  the  kind  of  plants  being  treated,  as  there  is 
considerable  difference  between  various  plants  as  to  their  resisting 
power  to  this  gas. 

Spraying  with  nicotine  liquids  — Nicotine  extracts  diluted  with 
water,  if  carefulty  applied  to  plants,  will  kill  large  numbers  of  the 
greenhouse  thrips,  but  the  great  objection  is  that  many  are  not  hit  by 
the  spray,  and  therefore  the  plants  become  infested  again  in  a short 
time. 

Spraying  with  kerosene  emulsion .b — It  is  quite  possible  that  kero- 
sene emulsion  spray  will  be  effective  against  the  greenhouse  thrips 
when  used  at  the  strength  of  1 part  of  stock  to  1 0 parts  of  water  and 
it  costs  considerably  less  and  is  more  readily  obtained  than  the  nico- 
tine preparations.  It  should  be  very  carefully  prepared  and  used 
experimentally  at  first  until  the  effect  on  the  foliage  of  the  different 
plants  is  noted.  Care  should  also  be  taken  to  prevent  a quantity  of 
emulsion  from  collecting  around  the  roots. 

Water  spray. — Frequent  treatment  with  a stiff  spray  of  water  from 
a garden  hose  will  tend  to  keep  this  insect  down,  but  unless  there  are 
only  a few  plants  it  would  be  better  to  use  one  of  the  other  remedies. 

Any  treatment  for  this  insect  should  be  repeated  in  from  7 to  10 
days  to  destroy  the  young  larvae  that  have  hatched  from  the  eggs. 
This  should  be  sufficient,  but  it  may  be  best  to  give  a third  treatment 
in  another  week  or  two. 

BIBLIOGRAPHY. 

1.  Bouche,  P.  F.c — Schadliche  Garten  Insecten,  p.  42,  1833. 

Original  description  of  the  species. 

2.  Haliday,  A.  H. — Entomological  Magazine,  Vol.  Ill,  p.  443,  1836. 

Description  of  the  female  as  Heliothrips  adonidum. 

3.  Burmeister,  H. — Handbuch  der  Entomologie,  Yol.  II,  p.  412,  1838. 

Description  of  adult  female  and  habits  of  insect. 

a For  complete  directions  for  the  use  of  hydrocyanic-acid  gas,  see  Cirs.  37  and  57, 
Bur.  Ent.,  U.  S.  Dept.  Agr. 

b For  the  method  of  making  emulsions,  see  Farmers’  Bulletin  127,  pp.  22-23,  or 
Cir.  80,  Bur.  Ent.,  U.  S.  Dept.  Agr. 

c Not  seen  by  author. 


THE  GREENHOUSE  THRIPS. 


59 


4.  Bormeister,  H. — Genera  Insectorum,  Fasc.  5,  1838. 

Short  description  and  excellent  colored  plate  of  the  adult  female. 

5.  Haliday,  A.  H. — Walker,  Homopt.  Ins.  Brit.  Mus.,  p.  1102,  PI.  VI,  fig.  13,  1852. 

Short  description  and  figures  of  parts  of  head. 

6.  Heeger,  E. — Fiinfte  Fortsetzung  Sitzungsb.  Kais.  Akad.  Wiss.,  Wien,  IX,  p.  473, 

PI.  XVII,  1852;  separate,  Wien,  Gerold,  VIII,  pp.  3-4,  1852. 

Description  of  egg  and  young  stages  and  adult  with  account  of  habits. 

7.  Bremi-Wolf,  J.  J. — Stett.  Ent.  Zeit.,  pp.  313-315,  1855. 

Reprinted  from  Abh.  Zurick  Gartenbau-Geselle,  111,  pp.  260-261.  Short  description  and 
account  of  habits. 

8.  Low,  F. — Verhandl.  k.  k.  zool.-bot.  Ges.,  Wien,  XVII,  p.  747,  1867. 

Brief  account  of  injury. 

9.  Boisduval,  J.  A. — Essai  sur  Entomologie  Horticole,  pp.  233-235,  fig.  32,  1867. 

Description  of  adult,  account  of  habits  with  long  list  of  host  plants,  and  figure  of  leaf  injured  by 
this  insect. 

10.  Packard,  A.  S. — 17th  Ann.  Rep.,  Mass.  Bd.  Agr.,  p.  263,  pi.  1,  fig.  2,  1870. 

Short  account  of  habits  of  this  insect  and  a poor  illustration  of  adult. 

11.  Cook,  A.  J. — 3rd  Ann.  Rep.  Pom.  Soe.  Mich.,  1873-74,  p.  501,  1874. 

Brief  notice  in  which  this  insect,  mentioned  as  Thrips  adonidum,  is  called  a serious  pest  in 
Michigan. 

12.  Packard,  A.  S. — Half  Hours  with  Insects,  pp.  118-119,  fig.  86,  1881. 

This  account  is  nearly  identical  with  No.  10. 

13.  Pergande,  Th. — Psyche,  Vol.  Ill,  p.  381,  1$82. 

Brief  note  on  occurrence  out  of  doors,  at  Washington,  D.  C.,  Nov.  14. 

14.  Lefevre,  E. — Entomologist,  Vol.  XV,  p.  240,  1882. 

Mentioned  as  injurious  to  greenhouse  plants. 

15.  Lintner,  J.  A. — 2nd  Rep.  Ins.  N.  Y.,  pp.  29,  31,  38,  56,  1885. 

There  is  some  doubt  as  to  whether  tbis  insect  or  a leaf-hopper  is  referred  to  in  the  first,  second, 
and  third  references. 

16.  . — Ann.  Soc.  Ent.  Belg.,  Vol.  XXIX,  p.  lxx,  1885. 

Note  on  use  of  tobacco  as  a fumigant. 

17.  Jordan,  K. — Zeitschrift  fur  Wiss.  Zool.,  XLVII,  pp.  541-620,  Pis.  XXXVI- 

XXXVIII,  1888. 

Anatomy  and  biology  of  Thysanoptera,  with  frequent  mention  of  this  insect. 

18.  Uzel,  J. — Monographie  der  Ordnung  Thysanoptera,  pp.  168-170,  PI.  VI,  figs.  90- 

92,  1895. 

Description  of  adult  and  figures  of  head,  antenna,  and  wing. 

19.  Pergande,  Th. — Insect  Life,  Vol.  VII,  p.  390,  1895. 

Observations  on  this  and  other  thrips. 

20.  Frank,  A. — Die  tierparasitaren  Krankheiten  der  Pflanzen,  p.  134,  1896. 

Short  account  of  habits  and  advice  as  to  remedies. 

21.  Davis,  G.  C. — Special  Bull.  No.  2,  Mich.  Agr.  Exp.  Sta.,  p.  13,  1896. 

Brief  note  on  occurrence  in  Michigan. 

22.  Buffa,  P. — Estratto  dalla  Rivista  di  Patologia  Vegetale,  VII,  Nos.  1-4,  pp.  94- 

108;  continued,  VII,  Nos.  5-8,  pp.  129-135,  136-142,  1898. 

Study  of  the  external  and  internal  anatomy  of  the  species.  Illustrated  by  5 plates. 

23.  Tumpel,  R. — Die  Geradfliigler  Mitteleuropas,  p.  290,  1901. 

Description  of  female  and  poor  figure  in  colors. 

24.  Chittenden,  F.  H. — Weekly  Florists’  Review,  April  17,  p.  739,  1902. 

Short  popular  article  on  thrips  in  greenhouses. 


60 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU — IX. 


25.  Hinds,  W.  E. — Proc.  U.  S.  Nat.  Mus.,  vol.  26,  p.  168,  1903.  Issued  as  separate  j 

No.  1318,  1902. 

Description  of  adult  and  account  of  habits  as  far  as  known. 

26.  Moulton,  Dudley. — Tech.  Ser.  12,  Part  III,  Bur.  Ent.,  U.  S.  Dept.  Agr.,  ] 

pp.  43,  51-52,  1907. 

Brief  notes  on  characters  and  habits.  Destructive  to  laurestinas  out  of  doors. 

27.  Franklin,  H.  J.~ Proc.  U.  S.  Nat.  Mus.,  Yol.  XXXIII,  p.  719,  1908. 

Notes  on  occurrence  out  of  doors  in  the  Barbados. 


o 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 
BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  VII. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


NEW  BREEDING  RECORDS  OF  THE 
COFFEE-BEAN  WEEVIL. 


BY 

E.  S.  TUCKER, 

Special  Field  Agent. 


Issued  August  5,  1909. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1909. 


CONTENTS. 


Page. 

Introduction 61 

Nature  of  injury  to  corn 61 

Notes  on  life  history  in  corn 63 

Occurrence  in  chinaberries;  parasites  63 

Habits  in  general 64 


ILLUSTRATIONS. 


PLATE. 

Page.  • 

Plate  III.  Work  of  the  coffee-bean  weevil  ( Arxcerus  fasciculatus)  in  cornstalks.  62 

TEXT  FIGURE. 

Fig.  18.  Coffee-bean  weevil  ( Arascerus  fasciculatus ):  Larva,  adult,  pupa 62 

iii 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  VII. 


Issued  August  5,  1909. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


NEW  BREEDING  RECORDS  OF  THE  COFFEE-BEAN  WEEVIL. 

( Arsecerus  fasciculatus  De  Geer.) 

By  E.  S.  Tucker, 

Special  Field  Agent. 

INTRODUCTION. 

While  making  field  observations  upon  the  cotton  boll  weevil  during 
the  past  season  (1908) , a large  plantation  situated  6 miles  south  of  Alex- 
andria, La.,  was  visited  on  September  18  and  again  on  December  4. 
On  my  first  visit  at  this  place  the  overseer  directed  my  attention 
to  the  work  of  strange  weevils  occurring  in  dried  cornstalks  in  fields 
adjacent  to  cotton.  Upon  examination  the  larval  and  pupal  stages 
and  sometimes  a few  adults  of  the  insects  were  found  in  the  pith,  at 
or  close  to  the  joints  (PI.  III).  These  specimens  were  identified  as 
the  coffee-bean  weevil  (Arsecerus  fasciculatus  De  Geer)  (fig.  18),  and 
the  selection  of  Cornstalks  for  breeding  purposes  places  the  species 
on  record  as  a new  enemy  to  be  encountered  in  cornfields. 

NATURE  OF  INJURY  TO  CORN. 

According  to  the  statements  of  the  overseer,  the  working  of  these 
weevils  in  cornstalks  during  the  past  year  was  more  noticeable 
than  in  the  preceding  season,  when  he  first  detected  the  insects  at 
work.  He  claimed  that  the  attacks  began  in  green  stalks  before  the 
corn  matured  and  thus  caused  stunted  ears.  Being  a close  observer, 
he  first  noticed  their  attacks  during  the  last  week  of  August,  while  the 
stalks  were  still  fresh  and  sappy,  although  the  leaves  had  begun  to 
dry.  These  facts  prove  beyond  question  that  the  larvae  were  hatched 
within  living  tissues  of  the  plants.  Furthermore,  he  expressed  a 
firm  belief  that  the  holes  made  by  these  insects  for  emergence  from 
the  stalks  afterwards  offer  a retreat  for  cotton  boll  weevils,  which 
may  enter  and  hibernate  in  the  pith.  Ilis  opinion  in  this  respect 
was  supported  by  the  claim  that  he  had  found  boll  weevils  in  such 
places  at  the  time  the  land  was  being  prepared  for  spring  planting. 

61 


G2  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

In  the  course  of  such  work  many  old  cornstalks  were  dragged  out  of 
the  dirt  that  had  been  thrown  over  them  by  means  of  a “ middle- 
buster  ” plow  used  for  breaking  the  ground  during  November  and 
December;  and  in  two  or  three  instances,  which  he  remembered  as 
having  occurred  in  February,  he  found  stalks  with  boll  weevils 
secreted  in  the  cavities  evidently  formed  by  the  stalk  pests. 

At  the  time  of  my  first  examination  the  emergence  holes  and  other 
signs  of  work  by  Arsecerus  fasciculatus  were  not  visible  unless  the 
leaves  were  stripped  from  the  stalks  as  they  stood  in  the  fields. 
Centers  of  infestation  were  then  located  in  different  parts  of  the 
fields  by  breaking  open  a number  of  stalks  to  ascertain  the  extent  of 
depredations.  As  most  of  the  ears  had  been  gathered,  inspection  of 
the  greater  part  of  the  fields  was  freely  made  and  infested  sections  of 
the  stalks  were  collected.  The  damaged  stalks  broke  easily  at  the 
joints  where  larvae  had  worked,  and  usually  but  one  injured  place 
was  found  on  a stalk.  All  attacks  by  the  weevils  at  this  time  were 


Fig.  i.8.— Coffee-bean  weevil  (Arsecerus  fasciculatus):  a,  Larva;  6, 

enlarged.  (From  Chittenden.) 


aauxt  or  oeeue; 


A OCA  OX  J 


confined  to  the  upper  joints.  These  damaged  joints  varied  in  thick-; 
ness  from  a little  more  than  an  inch  to  slightly  less  than  one-half; 
inch.  The  extra  thick  and  hard  structure  of  the  lower  joints  was  then 
thought  to  present  unsuitable  conditions  for  the  breeding  of  the 
weevils,  at  least  where  the  pith  incompletely  filled  the  stem.  Further 
developments  which  were  noted  on  my  second  examination  showed, 
however,  that  the  insects  had  bred  extensively  and  worked  down- 
ward into  the  lowest  joints,  their  tunnels  running  through  the  pith 
from  one  joint  to  another.  Since  all  stages  were  found  again,  the 
prospect  for  continual  breeding  of  the  weevils,  which  perhaps  depends 
upon  mild  weather,  seemed  to  be  assured  as  long  as  the  stalks  were 
not  destroyed.  As  previously  observed,  the  effects  of  their  wort 
were  most  noticeable  at  the  joints.  The  common  occurrence  o 
damaged  stalks,  which  were  readily  detected  on  account  of  the  emerl 
gence  holes  being  exposed  to  view  by  reason  of  the  partial  loss  of  thJ 
leaves,  indicated  that  the  infestation  was  widespread.  I 


Bui.  64,  Part  VII,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture 


Plate  III. 


Work  of  the  Coffee-bean  Weevil  iAr/£.cerus  fasciculatus)  in  Cornstalks. 

(Original.) 


library 

UNIVERSITY  Of  ILLINOIS 
URBANA 


NEW  BREEDING  RECORDS  OF  COFFEE-BEAN  WEEVIL. 


63 


NOTES  ON  LIFE  HISTORY  IN  CORN. 

Judging  from  the  appearance  of  damaged  stalks  when  split  open, 
the  larvae  evidently  begin  work  at  a joint  and  form  wide  cavities, 
mainly  in  a crosswise  direction,  as  they  progress  into  the  pith.  All 
\ examples  of  their  injuries  showed  that  irregular  portions  of  the  pithy 
substance,  excepting  most  of  the  fibers,  had  been  reduced  to  a dis- 
f colored,  powdery  condition,  which  was  usually  more  pronounced 
above  the  joint  than  below  it.  The  greater  part  of  the  time  neces- 
sary for  the  growth  of  the  grubs  is  probably  spent  in  the  exca- 
vation of  these  spaces  to  satisfy  their  demands  upon  the  pith  as 
a food  supply.  In  preparation  for  the  pupal  stage  the  grown  or 
nearly  grown  larvae  manifest  a tendency  to  burrow  into  fresh  pith 
ksome  distance  from  the  area  of  early  operations.  A considerable 
* proportion  of  them  does  this ; though  few  grubs  proceed  farther  than 
2 inches  upward  or  downward.  These  burrows  run  in  somewhat 
deflective  courses,  but  when  finished  always  terminate  just  under 
the  hard  surface  of  the  stem  and  afford  a convenient  position  at  the 
far  end  for  each  insect  upon  attaining  maturity  to  gnaw  its  way  out, 
( as  was  proved  in  many  cases  by  an  emergence  hole  being  already 
I cut  to  afford  means  of  escape  to  the  tenant.  Nearly  every  closed 
| burrow  contained  either  a grown  larva,  a pupa,  or  an  adult.  These 
stages  commonly  occurred  also  in  or  close  to  the  large  primary 
cavities,  indicating  that  not  all  the  larvae  undertake  special  meas- 
[ ures  for  pupation  away  from  their  original  place  of  development, 
\ though  all  apparently  provide  for  facility  of  emergence  as  adults,  and 
the  greater  number  perhaps  complete  their  transformations  in  the 
'same  relative  position.  In  fact,  the  greater  number  of  openings  ap- 
j pearing  through  the  surface  immediately  surrounding  the  worst 
damaged  places  close  to  the  joints  shows  that  emergence  is  most 
) frequently  effected  there. 

OCCURRENCE  IN  CHINABERRIES;  PARASITES. 

The  further  records  on  the  habits  of  Arsecerus  fasciculatus  are 
j obtained  from  the  notes  on  file  at  the  laboratory  of  the  Bureau  of 
j Entomology  at  Dallas,  Tex.,  all  of  which  pertain  to  the  breeding  of 
I the  species  in  berries  of  the  chinaberry  tree  ( Melia  azedarach).  Sev- 
eral larvae  and  pupae  and  one  adult  were  found  in  the  pulp  of  old 
i chinaberries  collected  at  Victoria,  Tex.,  April  24,  1907,  by  Mr.  R.  A. 
| Cushman.  From  other  collections  of  similarly  infested  berries,  made 
at  the  same  place  on  May  12,  by  Mr.  A.  C.  Morgan,  adult  weevils 
first,  emerged  seven  days  later,  and  on  the  27th  and  28th  of  the  same 
month  the  first  rearings  of  parasites  were  recorded.  These  para- 
sites represented  a species  which  was  later  described  by  Mr.  J.  C. 
Crawford  as  Cerambycobius  cusJimani,  and  further  developments  not 
only  proved  it  to  be  the  most  important  enemy  of  Arsecerus  fascicu- 


64 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


latus,  but  highly  inimical  to  the  cotton  boll  weevil.  Numbers  of 
these  parasites,  together  with  Eurytoma  tylodermatis  Ashm.,  which 
also  attacks  the  boll  weevil,  matured  during  the  following  June  and 
July  from  another  lot  of  old  berries  infested  by  the  immature  stages 
of  Arsecerus  fasciculatus , the  material  having  been  collected  by  Mr. 
Cushman  on  June  11.  Other  species  of  parasites  were  reared  from 
these  lots,  but  so  far  remain  undetermined.  The  latest  date  recorded  * 
for  the  emergence  of  weevils  in  confinement  was  July  11,  but  under  ; 
natural  conditions  these  insects  probably  breed  continuously  through- 
out  the  season  in  berries  which  are  apt  to  be  hanging  on  trees  or 
falling  from  them  at  all  times  of  the  year. 

During  the  past  year  opportunities  permitted  me  to  make  personal 
observations  upon  the  work  of  these  weevils  in  chinaberries.  While 
at  San  Augustine,  Tex.,  on  March  22,  my  attention  was  drawn  to  an  j 
infestation  occurring  in  both  fallen  and  hanging  berries.  Fallen  ber- 
ries in  a soft,  shriveled,  or  rotting  condition  frequently  contained  I 
well  advanced  larval  stages.  Seldom  were  more  than  one  or  two  j 
grubs  found  in  a berry.  The  larvae  in  hanging  berries  were  gener-  j 
ally  younger.  Some  of  the  hanging  berries  contained  very  small  , 
grubs,  evidently  newly  hatched,  that  had  scarcely  begun  working  in  ; 
the  firm  pulp.  The  falling  of  infested  berries  seemed  to  be  induced 
by  the  softened  condition  resulting  from  the  more  advanced  work  of  j 
the  larvae,  and  the  pupal  stage  must  necessarily  be  passed  in  fallen 
berries.  Collections  of  these  berries  were  placed  in  breeding  boxes, 
and  adult  weevils  emerged  from  April  16  until  June  16,  but  no  para- 
sites appeared,  probably  because  of  the  earliness  of  the  collection. 
On  March  25,  at  Longview,  Tex.,  the  species  was  again  taken  by  me,  ! 
but  only  fallen  berries  were  examined.  A live  adult  was  removed  j 
from  one  berry. 

At  Monroe,  La.,  on  the  21st  of  the  same  month,  Mr.  R.  A.  Cushman  i! 
made  an  interesting  find  in  regard  to  a new  enemy  of  the  coffee-bean  j 
weevil.  In  a number  of  infested  berries  one  weevil  larva  was  found  ?| 
to  be  attacked  by  a new  species  of  mite  belonging  to  the  genus 
Pediculoides.  This  mite  is  also  known  as  an  enemy  of  boll  weevil 
larvae. 

HABITS  IN  GENERAL. 

Previously  published  records  of  Arsecerus  fasciculatus  show  it  to  be  fj 
a common  insect  in  warm  climates,  and  that  it  has  no  particular  j| 
food  preferences.  It  is  as  likely  to  be  found  breeding  in  beans  or 
any  stored  dry  vegetable  products,  including  dried  fruits,  as  in  dry  I 
pithy  stalks,  and  is  commonly  found  breeding  as  a scavenger  in  dry  j | 
decayed  cotton  bolls.  In  common  with  most  other  weevils,  the  j 
adults  feign  death  for  a short  time  when  disturbed,  and  then  suddenly  » 
become  active  and  seek  to  escape. 


O 


/ 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 
BUREAU  OF  ENTOMOLOGY-  BULLETIN  No.  64,  Part  VIII. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  WOOLLY  WHITE-FLY: 

A NEW  ENEMY  OF  THE  FLORIDA  ORANGE. 


BY 

E.  A.  BACK,  Ph.  D., 

Agent  and  Expert. 


Issued  May  7,  1910. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1910. 


B UREAU  OF  ENTOMOLOG  Y. 

L.  O.  Howard,  Entomologist  and  Chief  of  Bureau. 

C.  L.  Marlatt,  Assistant  Entomologist  and  Acting  Chief  in  Absence  of  Chief. 

R.  S.  Clifton,  Executive  Assistant. 

Chas.  J.  Gilliss,  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truck  crop  and  stored  product  insect  investigations. 
A.  D.  Hopkins,  in  charge  of  forest  insect  investigations. 

W.  D.  Hunter,  in  charge  of  southern  field  crop  insect  investigations. 

F.  M.  Webster,  in  charge  of  cereal  and  forage  insect  investigations. 

A.  L.  Quaintance,  in  charge  of  deciduous  fruit  insect  investigations . 

E.  F.  Phillips,  in  charge  of  bee  culture. 

D.  M.  Rogers,  in  charge  of  preventing  spread  of  moths,  field  work . 

Rolla  P.  Currie,  in  charge  of  editorial  work. 

Mabel  Colcord,  librarian. 


ii 


CONTENTS. 


Page. 

Introduction 65 

Injury  and  extent  of  infestation 65 

Life  history 66 

Description 68 

Food  plants 70 

Distribution 70 

Natural  enemies 70 

Remedies 71 


ILLUSTRATIONS. 


PLATE . 

Plate  IV.  The  woolly  white-fly  ( Aleyrodes  howardi  Quaintance)  on  orange. 

Fig.  1. — Moderate  infestation  of  leaf  showing  many  specimens  in 
larval  instars.  Fig.  2. — Eggs  on  tender  leaf.  Fig.  3.— Heavy 
infestation  of  leaf,  showing  globules  of  honeydew  embedded  in 


woolly  secretions  overgrown  by  fungi 68 

TEXT  FIGURES. 

Fig.  19.  The  woolly  white-fly  ( Aleyrodes  howardi ):  Eggs,  female  ovipositing. . . 67 

20.  The  woolly  white-fly:  Larva,  first  instar 68 

21.  The  woolly  white-fly:  Details  of  larva  of  second  instr.r 69 

22.  The  woolly  white-fly:  Pupa-case  and  details 70 


iii 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  VIII. 


Issued  May  7,  1910. 


SOME  MISCELLANEOUS  RESULTS  OE  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  WOOLLY  WHITE-FLY:  A NEW  ENEMY  OF  THE  FLORIDA 

ORANGE. 

( Aleyrodes  howardi  Quaintance.) 

By  E.  A.  Back,  Ph.  D. 

Agent  and  Expert. 

INTRODUCTION. 

The  attention  of  entomologists  is  called,  for  the  first  time,  to  the 
discovery  in  this  country  of  a new  species  of  Aleyrodes  which  attacks 
citrus  trees.  In  view  of  the  widespread  havoc  played  among  the 
orange  groves  of  Florida  by  the  citrus  white-fly  (. Aleyrodes  citri  Riley 
and  Howard)  and  the  spot  ted- wing  white-fly  (. Aleyrodes  nubifera 
Berger),  the  appearance  among  the  orange  trees  at  Tampa  of  another 
aleyrodid  which  has  already  demonstrated  itself  to  be  of  economic 
importance  is  of  interest,  if  not,  indeed,  a subject  for  considerable 
concern. 

During  a recent  examination  of  orange  trees  along  several  of  the 
streets  in  the  business  section  of  Tampa  in  connection  with  govern- 
ment white-fly  investigations  that  are  being  carried  on  in  Florida  by 
the  Bureau  of  Entomology,  the  attention  of  the  writer  was  attracted 
to  dense  white  and  grayish  woolly  secretions  on  the  under  surface  of 
many  leaves.  At  first  this  was  supposed  to  be  a heavy  infestation  of 
the  rather  scarce  Paraleyrodes  jpersex  Quaintance,  but  on  closer  exami- 
nation proved  to  be  Aleyrodes  howardi  Quaintance,  up  to  the  present 
time  known  only  to  infest  orange  trees  on  several  of  the  West  Indian 
islands,  especially  Cuba. 

INJURY  AND  EXTENT  OF  INFESTATION. 

At  present  very  little  is  known  of  the  capacity  for  injury  possessed 
by  this  aleyrodid.  Mr.  C.  L.  Marlatt,  Assistant  Chief  of  the  Bureau 
of  Entomology,  found  it  quite  abundant,  locally,  on  several  of  the 
old  orange  trees  at  Artimisa,  Cuba,  but  at  that  time  (1905)  noted 

65 


66 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


that  it  had  spread  but  slightly  into  the  surrounding  younger  citrus 
groves.  When  describing  it  for  the  first  time  Prof.  A.  L.  Quaintance  a 
stated  that,  judging  from  its  abundance  on  leaves  sent  to  the  Bureau 
of  Entomology  from  Cuba,  it  was  a very  serious  pest  of  the  Cuban 
orange,  possibly  rivaling  the  well-known  citrus  white-fly  in  Florida. 
Whatever  damage  it  is  causing  in  Cuba,  where  it  may  be  partially 
held  in  check  by  parasites  and  predaceous  enemies,  it  has  shown  itself 
capable  of  rapid  multiplication  and  spread  in  its  new  home  at  Tampa. 
Notwithstanding  the  fact  that  it  has  not  been  observed  in  Florida 
before,  although  many  trees  now  heavily  infested  have  been  under 
casual  observation  during  1907  and  1908,  it  has  become  well  estab- 
lished over  a very  large  portion  of  the  city,  spreading  northward 
beyond  Michigan  avenue  and  eastward  about  2 miles,  into  Ybor  City. 
Orange  groves  in  the  more  elevated  portions  of  the  city  are  thoroughly 
infested,  hence  it  is  safe  to  presume  that  the  pest  is  well  established 
in  the  western  section  of  the  city. 

From  the  present  infestation  it  appears  that  the  insect  first  secured 
a foothold  along  the  water  front,  and  this  points  to  its  possible  impor- 
tation from  Cuba.  In  ^his  section  neglected  worthless  trees  along 
the  streets  and  in  dooryards  are  in  many  cases  heavily  infested.  While 
it  appears  to  be  rivaling  the  citrus  white-fly  in  the  extent  of  its  attack 
on  some  trees,  it  is  improbable  that  it  is  capable  of  causing  such 
widespread  disaster  : nevertheless,  if  it  becomes  abundant  in  a grove, 
it  will  prove  a source  of  no  little  aggravation  and  discomfort  to  those 
working  in  the  trees  because  of  the  large  and  extremely  viscid  drops 
of  honeydew  which  collect  over  the  bodies  of  the  insects,  and  later 
become  embedded  in  the  copious  waxen  secretions. 

LIFE  HISTORY. 

Nothing  has  been  published  regarding  the  life  history  of  this  aleyro- 
did  aside  from  the  statement  made  by  Professor  Quaintance  (1.  c.) 
that  the  eggs  lie  prostrate  on  the  leaf,  and  are  arranged,  more  or  less, 
in  circles  or  curves.  When  discovered  in  Tampa  by  the  writer  on 
November  14,  1909,  adults  were  abundant  and  depositing  eggs  upon 
both  new  and  old  growth,  showing  the  usual  preference  for  the  for- 
mer, and  larvae  in  all  stages,  as  well  as  pupae,  were  numerous.  Later, 
on  December  15,  Mr.  S.  S.  Crossman  found  adults  abundant,  and 
examination  of  material  at  this  time  showed  that  pupae  were  still 
maturing.  The  last  brood  of  adults  of  this  species  is,  therefore,  on 
wing  later  in  the  year  than  that  of  either  the  citrus  or  spotted-wing 
white-fly.  Adults  were  noted  by  the  writer  on  a visit  to  Tampa  dur- 
ing late  January. 

«U.  S.  Dept.  Agr.,  Bur.  Ent.,  Tech.  Ser.  12,  Pt.  V,  pp. 91-92, 1907.  The  more  impor- 
tant Aleyrodklse  infesting  economic  plants,  with  description  of  a new  species  infesting 
the  o ranee. 


Bui.  64,  Part  VIII,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture. 


Plate  IV. 


The  Woolly  White  Fly  (Aleyrodes  howardi)  on  Orange. 

Fig.  1.— Moderate  infestation  of  leaf,  showing  many  specimens  in  larval  instars.  Fig.  2.— Eggs  on 
tender  leaf.  Fig.  3. — Heavy  infestation  of  leaf,  showing  globules  of  honeydew  embedded  in  woolly 
secretions  overgrown  by  fungi.  (Original.) 


library 

UNIVERSITY  Of  ILLINOIS 
URbANA 


THE  WOOLLY  WHITE-FLY. 


67 


Unless  molested  or  crowded  each  female  deposits  her  eggs  in  a com- 
plete circle  (PL  IV,  fig.  2),  she  being  always  on  the  inside  (fig.  19,  c). 
This  arrangement  she  effects  by  using  her  mouth  parts  as  a pivot 
upon  which  to  rotate  her  body.  Since  often  as  many  as  3 or 
4 rows  of  eggs  are  present  in  one  circle,  it  is  evident  that  the  female 
describes  several  circles  while  ovipositing  before  seeking  a new  place. 
Although  as  few  as  27  eggs  have  been  counted  in  a single  circle  and 
as  many  as  130  in  a circle  of  4 rows,  it  is  probable  that  the  larger 
number  does  not  indicate  the  maximum  egg-laying  capacity,  which, 
in  the  case  of  A.  citri,  has  been  found  to  be  222. 

The  eggs  are  whitish  when  deposited  but  soon  turn  to  a dark-brown 
or  blackish  color  and  become  partially  covered  by  waxen  secretions 
rubbed  from  the  bodies  of  the  adults.  They  are  curved,  the  concave 
side  being  upward  (fig.  19,  a,  b),  and  in  hatching  the  membranes 
rupture  along  the  median  distal  half  of  the  upper  surface  and  do  not 
spring  back  into  place  after 
the  larva  has  escaped. 

The  larva  after  hatching 
crawls  about  before  settling. 

It  is  yellowish,  elliptical,  witli 
9 pairs  of  marginal  spines  and 
4 pairs  of  short,  stout,  dorsal 
spines.  Soon  after  ceasing 
to  crawl,  it  develops  a short, 
inconspicuous,  marginal  wax 
fringe  similar  to  that  of  the 
first  instar  of  A.  nubifera  (fig. 

20).  In  the  second  instar 
the  marginal  bristles  are  lost 
except  one  anterior  and  two  posterior  pairs,  and  the  legs  become 
unfit  for  locomotion  as  is  the  case  with  other  aleyrodids.  During 
this  instar  there  develop  6 white  abdominal  cross-bands  and  a 
distinct,  white,  marginal  fringe  of  wax,  varying  in  width  with  age, 
often  becoming  0.3  mm.  wide;  aside  from  these  secretions,  each  of 
the  dorsal  spines  secretes  a long,  outstanding  waxen  rod,  of  varying 
length,  these  rods  being  at  all  times  characteristic  of  this  instar 
(see  fig.  21).  After  passing  into  the  third  instar  the  larva,  except  in 
point  of  size,  assumes  the  appearance  of  the  pupa;  the  marginal 
fringe  and  abdominal  secretions  found  in  the  preceding  instar  remain 
practically  the  same,  but  these  are  largely  or  wholly  concealed  by 
the  long,  white,  curling,  and  variously  matted  secretions  which  arise 
from  along,  but  not  on,  the  margin  of  the  insect,  giving  to  a leaf 
infested  with  this  species  a woolly  appearance  (PL  IV,  fig.  1)  which, 
when  infestation  is  heavy,  entirely  conceals,  the  insect  beneath.  These 
threadlike  secretions  are  often  twice  as  long  as  the  insect  itself.  At 


Fig.  19. — The  woolly  white-fly  ( Aleyrodes  howardi ):  a, 
Egg,  showing  attachment  to  leaf;  b,  eggshell,  viewed 
from  above;  c, female  depositing  eggs  in  a circle,  c,  Much 
enlarged;  a,  6,  highly  magnified.  (Original.) 


68 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


emergence  the  pupa  case  splits  at  the  anterior  end,  down  both  the 
dorsal  and  ventral  sides  along  the  median  line,  on  the  dorsal  side 
splitting  back  to  the  first  abdominal  segment.  The  empty  pupa 
case  is  white  and  delicate.  The  adult  insect  of  either  sex  is  lemon- 
yellow,  with  pure- white  wings,  without  darker  markings;  the  ground  . 
color  of  the  body  being  partially  obscured  by  loose  particles  of  waxen 
secretions.  The  adult  resembles  closely  A.  citri,  the  citrus  white-fly,  ; 
but  carries  its  wings  farther  away  from  the  body,  thus  leaving  more 

of  the  abdomen  exposed. 

A very  characteristic  feature  of 
this  species,  as  compared  with 
any  of  the  Florida  Aleyrodidse  now 
known  to  the  writer,  is  the  globule 
of  honeydew  which  collects  over 
the  vasiform  orifice,  often  becoming 
so  large  as  to  conceal  the  posterior 
half  of  the  body,  and  resembling 
somewhat  the  secretions  of  the 
persimmon  Psylla.  These  globules 
are  extremely  viscid  and  make  the 
handling  of  leaves  infested  with  this 
aleyrodid  very  disagreeable.  They 
collect  in  large  numbers  in  the 
waxen  secretions  on  heavily  infested 
leaves  (Pl.  IV,  fig.  3)  and  both 
they  and  the  secretions  become 
grayish  and  dust-laden  with  age. 
The  globules  frequently  become 
overgrown  by  a rank  growth  of 
greenish-brown  fungus  resembling 
the  hyperparasitic  species  attacking 
the  yellow  white-fly  fungus,  Ascher- 
sonia  fiavocitrina. 

DESCRIPTION. 

A detailed  description  of  Aleyrodes  howardi  follows  a : 

The  egg. — Length,  0.2  mm.  to  0.19  mm.;  width,  0.1  mm.  to  0.088  mm.  Uniformly 
brownish  in  color,  smooth,  without  reticulations  or  waxy  secretions;  curved,  lying 
prostrate  on  leaf,  with  convex  side  approximating  latter,  attached  by  short  stalk 
arising  from  convex  surface  about  one-fourth  distance  from  base  to  tip  of  egg.  Eggs 
deposited  more  or  less  in  complete  circles;  spaces  between  eggs  often  filled  with 
waxy  secretions  rubbed  from  body  of  adults.  (See  fig.  19.) 

a The  original  description  of  the  pupa  by  Professor  Quaintance  has  been  used  but 
amplified  by  the  writer. 


Fig.  20. — The  woolly  white-fly:  Larva  of  first 
instar,  dorsal  view,  showing  spines  and 
. marginal  wax  fringe.  Highly  magnified. 
(Original.) 


THE  WOOLLY  WHITE-FLY. 


69 


The  larva,  first  instar. — Size  about  0.26  mm.  by  0.13  mm. ; elliptical,  yellowish-white, 
with  9 pairs  of  short  marginal  bristles,  arranged  as  in  figure  20,  the  two  posterior  pairs 
longest,  the  relative  lengths  being  as  follows: 


Pair 1 2 3456789 

Relative  lengths 2 2. 5 6455488 


After  settling,  an  inconspicuous,  transparent,  marginal  wax  fringe  develops,  but 
little  exceeding  in  width  the  length  of  the  marginal  spines.  Eyes  reddish-brown,  usual. 
Dorsum  with  4 pairs  of  short  stout  spines;  1 pair  cephalad  and  mesad  of  eyes,  1 pair 
at  vasiform  orifice,  and  2 pairs  on  central  region  between  the  fifth  and  sixth,  and  sixth 
and  seventh  pairs  of  marginal  spines,  respectively.  Legs  and  antennse  well  devel- 
oped, usual;  vasiform  orifice  similar  in  shape  to  that  of  pupa,  but  without  apparent 
strong  setae. 

The  larva , second  instar. — Size,  about  0.38  mm.  by  0.22  mm.  All  marginal  bristles 
lost  except  2 pairs  of  minute  bristles,  one  at  anterior,  the  other  at  posterior  end  of  body. 
Four  pairs  of  bristles  on  dorsum  located  as  in  first  instar,  but  different  in  that  when 
wax  secretions  are  removed,  the  first  3 anterior 
pairs  are  stout  spindle-shaped  (fig.  21,  a),  the 
fourth  pair  at  vasiform  orifice,  long  and  slender,  as 
in  pupal  stage:  a fifth  dorsal  pair  at  caudal  end  of 
body  but  not  on  margin,  similar  to  those  in  pupal 
stage.  Color,  brownish  or  black;  margin  with 
narrow  white  wax  fringe,  equaling  at  times 
0.3  mm.  Instar  conspicuous  because  of  long 
single,  stout,  outstanding  waxen  rods  secreted 
by  each  of  the  spindle-shaped  dorsal  spines, 
and  6 abdominal  cross  bands  of  white  waxen 
secretions.  Insects  well  advanced  in  this  instar, 
after  the  dorsal  waxen  rods  have  developed,  pre- 
sent a profile  similar  to  that  shown  in  figure  21, 
at  b. 

The  larva,  third  instar. — Size,  about  0.58  mm. 
by  0.38  mm.  Except  in  point  of  size,  this  re- 
sembles the  pupal  instar  in  all  respects.  The 
spindle-shaped  spines  of  the  previous  instar  are 
replaced  by  ordinary  strong  bristles. 

The  pupa. — Size,  about  0.9  by  0.55  mm.,  sub- 
elliptical in  shape.  Many  specimens  with  more 
or  less  evident  indentures  on  cephalo-lateral 
margin  of  case,  with  cephalic  end  obtusely  pointed.  Color,  on  leaf,  under  hand 
lens,  with  secretions  removed,  yellowish-brown  varying  to  blackish;  under  transmitted 
light,  yellowish  to  brownish-yellow.  There  is  a distinct  marginal  rim  all  around, 
with  wax  tubes  distinct,  the  incisions  acute  and  tubes  rounded  distally.  From 
margin  of  case  all  around  arises  a short  rim  of  wax,  composed  of  individual  wax- 
threads,  serrated  on  margin  as  seen  under  a high-power  microscope.  Pupa  usually 
quite  covered  by  a very  copious  secretion  of  whitish,  curling  wax-rods  which  is 
very  conspicuous  in  badly  infested  leaves,  quite  hiding  the  insects  beneath  (Plate  IV, 
fig.  3);  these  waxen  filaments  often  much  greater  in  length  than  the  insect’s  body, 
spreading  outward  when  insects  are  not  crowded,  but  upward  when  crowded;  and 
arising  from  along  the  outer  portion  of  the  case,  but  not  on  the  margin  itself  from 
which  the  above-mentioned  distinct  waxen  fringe  arises.  Dorsum  of  pupae  with 
many  wax-secreting  pores;  the  secretions  very  short,  irregular  upon  the  cephalothoracic 
region,  and  on  the  abdominal  portion  arranged  in  cross  bands  on  each  segment,  being 


Fig.  21.— The  woolly  white-fly,  second 
larval  instar,  a.  Spindle-shaped  spine;  b, 
diagrammatic  profile,  showing  character- 
istic wax  secretions.  Highly  magnified. 
(Original.) 


70 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


most  dense  on  the  middle  of  the  segments.  Denuded  of  secretions,  the  pupa  case 
is  seen  to  be  at  first  almost  flat,  but  later  becoming  rather  convex  as  the  insect 
develops,  with  segments  distinct. 

Dorsum  with  pair  (1)  of  strong  setae  on  first  abdominal  segment,  a pair  (2)  at  vasi- 
form  orifice,  and  a pair  (3)  at,  but  not  on,  caudal  margin  extending  some  distance 
beyond  margin  of  case.  There  is  also  a pair  of  minute  marginal  spines  (a)  at  the 
anterior  end,  and  another  (b)  at  the  posterior  end  of  body.  The  relative  lengths  of 
these  spines  are  as  follows: 

Pair 1 2 3 a b 

Relative  lengths 14  16  10  1.5  2.5 

There  is  also  a pair  of  small  bristles  on  the  venter  beneath  the  vasiform  orifice. 
Vasiform  orifice  relatively  small,  subcordate,  the  rim  dark  brown,  from  6 to  8 strong 

setae  or  spines  arising  from  caudal 
margin;  operculum  largely  filling  ori- 
fice, the  distal  margin  with  two  faint 
notches;  lingula  not  distinguishable. 
(See  fig.  22.) 

The  adult. — Usual,  lemon  - yellow, 
after  emergence  becoming  coated  with 
white  waxen  secretions;  wings  pure 
white,  without  darker  markings,  held 
along  sides  of  abdomen,  but  not 
meeting  over  the  dorsum.  A con- 
siderable amount  of  flocculent  white 
wax  is  secreted,  but  not  as  copious 
a supply  as  is  secreted  by  the  adult 
of  P.  perseae.  In  female:  Length  of 
body,  0.42  to  0.47  mm.;  length  of  fore 
wing,  1.1  mm.;  width  of  fore  wing, 
0.36  mm.;  length  of  antenna,  0.31 
mm.;  length  of  hind  tibia,  0.035 
mm.;  relative  lengths  of  antennal  segments  as  follows: 


Segment 1 2 3 4 5 6 7 Spine. 

Relative  lengths 1.5  3 10  1.3  2.5  2.6  1.5  0.7 


FOOD  PLANTS. 

The  woolly  white-fly  infests  the  various  species  of  citrus,  the 
guava,  and  the  mango.  While  found  on  the  mango  at  Tampa  by 
the  writer,  its  presence  on  this  plant  is  probably  the  result  of  acci- 
dent. Mr.  W.  L.  Tower  is  authority  for  its  occurrence  on  guava  in 
Porto  Rico. 

DISTRIBUTION. 

This  species  occurs  on  several  islands  of  the  West  Indies,  but 
more  especially7  in  Cuba.  It  is  now  established  at  fl  ampa,  Fla. 

NATURAL  ENEMIES. 

While  no  predaceous  insects  are  known  to  attack  this  aleyrodid, 
Cook  and  Horn®  have  reported  it  parasitized  by  the  “red  fungus,” 

aCook,  M.  T.,  and  Horne,  W.  T.,  Cuban  Exp.  Sta.  Bui.  9,  p.  31,  1908. 


Fig.  22. — The  woolly  white-fly:  Pupa  case  and  details. 
Greatly  enlarged . ( From  Quaintance. ) 


THE  WOOLLY  WHITE-FLY. 


71 


Aschersonia  aleyrodis,  in  Cuba,  and  Mr.  W.  L.  Tower,  entomologist  of 
the  Porto  Rican  Experiment  Station,  reports  that  in  Porto  Rico  it 
is  held  in  check  by  fungi  (undetermined). 

REMEDIES. 

So  far  as  known  to  the  writer  no  remedial  measures  have  been 
adopted  against  this  pest  up  to  the  present  time.  Its  recent  dis- 
covery has  not  made  it  possible  for  experiments  leading  to  its  con- 
trol to  be  concluded  although  such  experiments  are  now  in  progress. 
From  present  indications  it  seems  probable  that  this  white-fly  will 
be  more  easily  controlled  by  fumigation  than  by  spraying,  inasmuch 
as  when  nearly  mature  it  is  very  well  protected  from  spray  liquids 
by  the  secretions  mentioned  above.  Present  indications  are  that 
during  the  early  larval  instars  it  is  as  well  controlled  by  spraying 
as  are  the  citrus  and  the  spotted-wing  white-flies,  with  which  it  is 
found  associated. 


O 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  IX. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


NOTES  ON  A COLORADO  ANT. 


BY 

H.  O.  MARSH, 

Agent  and  Expert. 


Issued  October  17,  1910. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1910. 


BUREAU  OF  ENTOMOLOGY. 


L.  O.  Howard,  Entomologist  and  Chief  of  Bureau. 

C.  L.  Marlatt,  Assistant  Entomologist  and  Acting  Chief  in  Absence  of  Chief. 

R.  S.  Clifton,  Executive  Assistant. 

W.  F.  Tastet,  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truck  crop  and  stored  product  insect  investigations. 
A.  D.  Hopkins,  in  charge  of  forest  insect  investigations. 

W.  D.  Hunter,  in  charge  of  southern  field  crop  insect  investigations. 

F.  M.  Webster,  in  charge  of  cereal  and  forage  insect  investigations. 

A.  L.  Quaintance,  in  charge  of  deciduous  fruit  insect  investigations. 

E.  F.  Phillips,  in  charge  of  bee  culture. 

D.  M.  Rogers,  in  charge  of  preventing  spread  of  moths , field  work. 

Rolla  P.  Currie,  in  charge  of  editorial  work 

Mabel  Colcord,  librarian. 

ii 


CONTENTS. 


Page. 

Introduction 73 

Injurious  babits 73 

Experiments  with  potassium  cyanid  as  a remedy 74 


hi 


U.  S.  D.  A.,  B.  E.  Bui.  64,  Part  IX. 


Issued  October  17, 1910. 


I 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


NOTES  ON  A COLORADO  ANT. 

( Formica  cinereorufibarbis  Forel.) 

By  H.  O.  Marsh, 

Agent  and  Expert. 

INTRODUCTION. 

A medium-sized  ant,  known  scientifically  as  Formica  cinereorufi- 
barbis Forel,  is  one  of  the  most  common  species  occurring  in  the  vicin- 
ity of  Rocky  Ford,  Colo.  The  nests  which  it  constructs  along  the 
fences  and  irrigation  ditches  are  mounded  up  very  little  or  not  at  all, 
but  often  cover  a considerable  area.  Sometimes  these  nests  are  3 or 
4 feet  in  length  by  2 or  3 feet  in  width,  and  they  always  have  several 
openings. 

During  the  growing  season  this  species  of  ant  is  always  to  be 
found  in  attendance  on  various  species  of  aphides  or  plant  lice. 
During  the  summer  of  1909  it  was  most  commonly  found  together 
with  the  melon  aphis  ( Aphis  gossypii  Glov.)  on  cucurbits,  and  with 
CJiaitofihorus  populicola  Thos.  on  cottonwood.  The  ants  were  also 
observed  attending  a species  of  Membracidse  on  alfalfa,  and  late  in 
the  season  after  the  leaves  had  fallen  great  numbers  were  found 
clustered  and  feeding  upon  crushed  overripe  cantaloupes,  sometimes 
out  in  the  field  25  yards  from  any  ant  nests. 

As  the  ants  were  almost  invariably  to  be  found  on  aphis-infested 
cantaloupe  vines,  many  of  the  growers  are  of  the  opinion  that  they 
are  responsible,  in  part  at  least,  for  the  spread  of  the  aphides  from 
one  vine  to  another.  There  is  also  a rather  general  idea  that  the 
ants  take  the  aphides  into  their  nests  in  the  fall,  protect  them  through- 
out the  winter,  and  then  bring  them  out  in  the  spring  and  put  them 
upon  the  plants. 

INJURIOUS  HABITS. 

There  appears  to  be  but  little  foundation  for  believing  that  the 
ants  harbor  the  melon  aphis  during  the  winter,  and  after  careful 
watching  the  writer  has  never  seen  any  aphides  being  carried  into  the 


58603°— Bull.  64,  pt.  9-10 


73 


74 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU — IX. 


nests.  However,  these  ants  do  protect  the  aphides  from  their  natural 
enemies  on  the  growing  plants,  and  it  is  a common  thing  to  see  the 
ants  busily  engaged  in  killing  and  carrying  off  the  syrphid  larvae, 
which  were  doing  good  work  in  destroying  the  “lice.”  They  were 
also  repeatedly  observed  carrying  away  adults  of  the  convergent  lady- 
bird ( Hi'p'podamia  convergens  Guer.),  the  nabid  bug  Reduviolus  ferns 
L.,  and  a species  of  Chrysopa.  The  ladybird  larvae  apparently  were 
not  molested,  while  the  beneficial  syrphid  larvae  were  objects  of  special 
attack,  and  it  was  not  unusual  to  see  as  many  as  ten  or  twelve  larvae 
being  carried  away  from  a single  vine  at  a time.  Wherever  the  ants 
were  abundant  the  syrphid  larvae  were  noticeably  reduced  in  number, 
and  the  aphides  thus  had  a better  chance  of  increasing.  The  ants 
appear  to  use  the  syrphid  larvae  as  food,  as  they  were  observed  carry- 
ing them  into  their  nests,  which,  in  several  cases,  were  12  or  15  feet 
from  the  vines  infested  by  the  aphides. 

EXPERIMENTS  WITH  POTASSIUM  CYANID  AS  A REMEDY. 

As  frequent  inquiries  were  made  by  the  melon  growers  concerning 
possible  remedies  for  use  against  the  ants  it  was  decided  to  conduct 
a series  of  experiments.  Owing  to  the  large  number  of  nests  which 
occur  along  practically  every  fence  and  ditch,  and  to  the  large  size 
of  the  nests,  and  particularly"  to  the  fact  that  each  nest  has  several 
openings,  it  was  obvious  that  carbon  bisulphid  would  be  too  expen- 
sive for  practical  use  with  this  species,  and  it  was  decided  to  make 
the  experiments  with  various  solutions  of  potassium  cyanid.  The 
object  of  these  experiments  was  to  determine  if  repeated  applications 
would  materially  reduce  the  number  of  the  ants  and,  if  the  ants  were 
thus  reduced,  what  effect  it  would  have  on  the  melon-aphis  problem. 

In  making  these  experiments  a strip  about  80  yards  in  length 
was  selected  along  a fence  at  the  edge  of  a cantaloupe  field.  This  strip 
was  bordered  along  one  side  by  a common  road  or  highway  and 
occupied  along  the  center  by  a row  of  elm  trees  which  were  too 
small  to  cause  any  shade  worth  mentioning,  as  none  of  them  was  over 
4 inches  in  diameter  at  the  base.  There  were  at  least  twenty-five 
distinct  nests  in  this  strip,  and  the  ants  occurred  by  thousands. 
Cantaloupes  had  been  planted  in  the  field  along  this  strip  for  several 
successive  years,  and  each  year  the  first  few  rows  nearest  the  fence 
were  infested  by  melon  “lice,”  while  the  vines  which  were  beyond 
the  convenient  range  of  the  ants  were  not  infested,  or  at  least  not 
until  later  in  the  season.  The  owner  of  the  cantaloupes  was  firmly 
convinced  that  the  ants  were  responsible  for  the  infestation  of  the 
first  few  rows  and  welcomed  any  attempt  to  destroy  them. 

In  order  to  determine  the  cheapest  and  most  practical  solution  the 
following  preliminary  tests  were  made: 


NOTES  ON  A COLORADO  ANT. 


75 


Experiment  No.  1. — One-half  ounce  of  98  per  cent  cyanid  of  potash 
dissolved  in  1 gallon  of  water  was  used.  On  August  31, 1909,  at  5 p.  m., 
2 gallons  of  this  solution  were  applied  to  a nest  2\  feet  in  length  by 
2 feet  in  width.  The  entire  outer  surface  of  the  nest  was  soaked  and  a 
considerable  quantity  was  poured  directly  into  the  openings.  Ants 
which  were  hit  died  almost  at  once  and  others  which  returned  from 
the  field  and  ran  over  the  wet  surface  died  within  a few  seconds. 
When  the  nest  was  examined  an  hour  later  the  surface  was  well 
covered  with  dead  specimens.  There  was  still  a fairly  strong  odor 
of  the  cyanid  from  the  wet  soil  and  returning  ants  were  soon  killed, 
although  they  did  not  die  quite  as  rapidly  as  when  the  application 
was  first  made. 

Experiment  No.  2. — One  ounce  of  98  per  cent  cyanid  in  1 gallon  of 
water  was  used.  On  August  31,  between  5.30  and  5.45  p.  m.,  4 
gallons  of  this  solution  were  applied  to  two  nests,  each  about  3 feet 
long  and  2 feet  wide.  The  conditions  were  as  in  Experiment  No.  1 
and  the  immediate  results  appeared  to  be  about  the  same. 

Experiment  No.  3. — Two  ounces  of  98  per  cent  cyanid  in  1 gallon 
of  water  were  used.  On  August  31,  at  6 p.  m.,  2 gallons  of  this 
solution  were  applied  to  a nest  about  3 feet  long  by  2 feet  wide. 
The  immediate  results  appeared  to  be  about  the  same  as  in  Experi- 
ments Nos.  1 and  2,  although  there  was  a somewhat  stronger  odor 
of  the  cyanid  from  the  wet  soil. 

At  the  time  these  three  tests  were  made  the  sun  was  warm  and 
shining  brightly.  The  ants  were  very  active  and  thousands  of  them 
were  away  from  the  nests  and  among  the  aphis-infested  cantalouoe 
vines. 

Since  the  larger  lumps  of  cyanid  dissolved  rather  slowly  some 
time  was  gained  by  breaking  them  up  with  a hammer. 

At  4 p.  m.  on  September  1 an  examination  was  made  of  the  nests 
treated  in  these  tests.  At  that  time  there  were  hundreds  of  dead  ants 
lying  on  the  surface  of  the  nests  and  a comparatively  small  number 
of  specimens  was  running  about.  Most  of  the  living  ants  had  appar- 
ently lost  interest  in  the  aphides  and  had  gathered  on  or  about  the 
treated  nests  and  some  were  carrying  dead  specimens.  There 
appeared  to  be  little  difference  between  the  results  of  Experiments 
Nos.  1 and  2,  but  there  were  certainly  fewer  live  ants  about  the  nest 
treated  in  Experiment  No.  3 than  about  the  others. 

As  some  fear  was  felt  that  a strong  solution  of  the  cyanid  might 
kill  the  small  elm  trees  which  occupied  the  ant-infested  strip  and  as 
Experiment  No.  1 gave  comparatively  good  results,  it  was  concluded 
to  continue  the  work  with  that  strength.  Accordingly,  between 
4.30  and  6 p.  m.  on  September  1,  the  remainder  of  the  infested  strip, 
about  65  yards  in  length  and  containing  21  nests,  was  treated  with 


76 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


28  gallons  of  the  solution  at  the  rate  of  one-half  ounce  of  98  per  cent 
cyanic!  to  each  gallon  of  water.  At  the  time  of  this  treatment  there 
were  thousands  of  ants  either  actually  in  attendance  on  the  “lice” 
or  running  about  between  the  nests  and  the  infested  cantaloupe  vines. 

At  6 p.  m.  on  September  2 the  treated  strip  was  examined.  Dea  l 
ants  by  thousands,  at  some  places  in  heaps,  were  lying  on  or  about 
the  nests.  Many  dead  specimens  were  also  found  out  in  the  field 
from  6 to  10  feet  from  the  nests.  However,  at  every  nest  there  were 
still  a few  live  ants.  Practically  all  of  these  survivors  had  gathered 
about  the  nests  and  it  was  difficult  to  find  a live  ant  out  in  the  field, 
where  at  the  time  of  the  treatment  they  occurred  in  surprisingly  large 
numbers. 

In  order  to  test  the  effect  of  a second  treatment  applied  soon  after 
the  first,  two  nests  near  the  center  of  the  strip  were  given  a second 
application  at  5.30  p.  m.  September  3.  This  was  considered  as 
Experiment  No.  4.  In  this  experiment  2 gallons  of  solution  at  the 
rate  of  one-half  ounce  cyanid  to  each  gallon  of  water  were  applied 
to  each  nest  as  before. 

An  examination  made  of  these  nests  on  the  following  afternoon 
(September  4)  showed  that  although  a few  additional  ants  had  been 
killed  no  practical  advantage  had  been  gained  by  this  treatment, 
and  this  conclusion  was  not  altered  by  frequent  later  examinations. 

Along  the  entire  treated  strip  the  ants  which  remained  alive  seemed 
demoralized  for  about  a week,  but  by  September  11  several  small  col- 
onies had  again  started.  The  cyanid  solution  does  not  penetrate  very 
deeply  into  the  nests  and  it  is  evident  that  the  pupae  escape  destruc- 
tion unless  they  are  very  close  to  the  surface,  and  on  reaching  ma- 
turity they  are  able,  with  the  remaining  live  ants,  to  reestablish  the 
colonies. 

By  September  16  one  or  two  of  these  colonies  (nests)  had  reached 
fairly  good  size  and  although  the  ants  were  moderately  common 
they  occurred  in  very  much  smaller  numbers  than  they  did  at  the 
time  of  the  first  general  treatment  (September  2).  This  first  treat- 
ment left  the  nests  with  a “crust”  of  compact  soil  over  the  surface. 
At  two  or  three  nests,  just  under  the  crust,  the  ants  had  large  numbers 
of  pupae  and  at  a few  other  nests  a considerable  number  of  winged 
adults  had  crawled  out  and  was  clustered  about  the  openings. 

At  this  date  (September  16)  all  the  nests  in  the  entire  strip  were 
again  treated  with  25  gallons  of  the  solution  at  the  rate  of  one-half 
ounce  of  98  per  cent  cyanid  to  each  gallon  of  water.  A particular 
effort  was  made  to  soak  the  winged  specimens  and  the  pupae.  All  the 
adults  touched  were  readily  killed,  but  the  pupae  showed  no  immediate 
effect  from  the  treatment. 

An  examination  made  on  the  following  afternoon  showed  that 
although  the  number  of  ants  had  been  very  considerably  reduced 


NOTES  ON  A COLORADO  ANT. 


77 


there  were  still  some  living  specimens  at  each  nest.  The  pupae  at  the 
treated  nests  seemed  to  be  dead  and  the  living  ants  paid  no  attention 
to  them.  It  was  observed  that  at  two  places  quite  a number  of 
pupae  had  been  overlooked  and  not  soaked  by  the  solution  and  at 
another  place  a moderate  number  of  winged  specimens  had  crawled 
from  an  opening  of  an  untreated  (overlooked)  nest. 

By  September  27  about  a dozen  small,  weak  colonies  had  started, 
and  on  the  following  day  between  4 and  5 p.  m.  all  the  inhabited  nests 
were  again  treated  with  25  gallons  of  the  solution  at  the  rate  of  one- 
half  ounce  of  98  per  cent  cyanid  to  each  gallon  of  water.  In  this 
treatment  all  the  openings  in  the  nests  were  enlarged  with  a pointed 
stick  and  from  a quart  to  a gallon  of  the  solution  poured  into  each. 
At  this  date  many  of  the  cantaloupe  vines  had  been  trampled  down 
by  the  pickers  or  had  died  from  disease  or  other  cause.  As  a result 
there  was  not  a very  good  supply  of  aphides  in  the  immediate  vicinity 
of  the  nests  and  the  ants  were  mostly  close  about  or  in  the  nests. 
At  two  places  many  pupae  were  present  and  at  another  nest  there  were 
a good  many  winged  specimens. 

Examination  made  on  the  following  day  (September  29)  showed 
that  there  were  still  a few  living  ants  about  the  nests,  and  the  pupae 
were  still  light  in  color  and  did  not  appear  to  be  dead.  A day  later 
some  of  the  pupae  appeared  to  be  still  alive,  but  as  all  of  these  were 
embedded  in  the  moist  soil,  where  the  living  ants  paid  no  attention 
to  them,  they  certainly  could  not  have  survived.  At  this  time  there 
was  no  odor  of  the  cyanid  over  the  nests,  but  when  lumps  of  the 
moist  soil  were  picked  up  the  odor  from  them  was  quite  apparent. 

Repeated  examinations  made  of  the  treated  strip  during  October 
and  November  showed  that  the  ants  had  almost  completely  disap- 
peared, while  at  untreated  (check)  nests  they  occurred  in  large  num- 
bers. It  would  be  interesting  to  know  what  became  of  the  few 
specimens  which  survived  the  last  treatment.  Possibly  they  became 
discouraged  and  went  to  less  troubled  quarters. 

It  is  evident  that  from  experiments  of  this  nature  definite  or  final 
conclusions  can  not  yet  be  reached.  The  work  was  begun  so  late 
in  the  season  that  the  rather  gradual  decrease  in  the  number 
of  the  ants  had  no  marked  effect  on  the  melon  aphis.  It  showed 
that  to  keep  this  species  within  reasonable  bounds  repeated  appli- 
cations of  the  cyanid  and  constant  watching  are  necessary.  As 
this  would  require  so  much  more  attention  than  the  ordinary  farmer 
can  be  induced  to  give,  it  does  not  seem  probable  that  this  method 
will  ever  become  very  popular  for  this  particular  species  of  ant, 
unless  it  can  be  definitely  proved  that  this  species  is  a more  important 
factor  in  the  melon-aphis  problem  than  it  is  now  known  to  be.  It  is 
very  probable  that  quicker  results  would  have  been  obtained  if  a 
stronger  solution  had  been  used. 


78  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

At  Rocky  Ford,  Colo.,  98  per  cent  potassium  cyanid  was  obtainable 
in  small  lots  for  50  cents  a pound.  When  used  at  the  rate  of  a pound 
in  30  or  32  gallons  of  water  this  makes  a comparatively  cheap  solution. 

Although  this  solution  is  extremely  poisonous,  there  need  not  be 
undue  risk  to  human  beings  from  its  use  if  proper  care  is  exercised 
in  preparing  and  handling  it.  When  leaning  over  a half  barrel  of  the 
solution  for  the  purpose  of  stirring  it  or  dipping  out  pailfuls,  the 
fumes  were  quite  noticeable  and,  with  the  writer,  caused  a slight  dull 
headache  which  lasted  a short  time.  Although  in  applying  the  solu- 
tion the  writer's  hands  were  frequently  wet  with  it,  and  no  ill  effects 
resulted,  yet  it  would  be  safer  to  keep  the  solution  from  coming  into 
contact  with  the  skin.  Some  persons  are  peculiarly  susceptible  to 
this  poison,  and  with  some  its  contact  with  the  skin  causes  a rash. 
Persons  with  weak  hearts  should  be  especially  careful  not  to  inhale 
the  fumes. 

o 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  64,  Part  X. 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  PECAN  CIGAR  CASE-BEARER., 


BY 

H.  M.  RUSSELL, 

Agent  and  Expert. 


Issued  November  12,  1910. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1910. 


B UREA  U OF  ENTOMOLOGY. 


L.  O.  Howard,  Entomologist  and  Chief  of  Bureau. 

C.  L.  Marlatt,  Assistant  Entomologist  and  Acting  Chief  in  Absence  of  Chief. 
R.  S.  Clifton,  Executive  Assistant. 

W.  F.  Tastet,  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truck  crop  and  stored  product  insect  investigations. 
A.  D.  Hopkins,  in  charge  of  forest  insect  investigations. 

W.  D.  Hunter,  in  charge  of  southern  field  crop  insect  investigations . 

F.  M.  Webster,  in  charge  of  cereal  and  forage  insect  investigations. 

A.  L.  Quaintance,  in  charge  of  deciduous  fruit  insect  investigations. 

E.  F.  Phillips,  in  charge  of  bee  culture. 

D.  M.  Rogers,  in  charge  of  preventing  spread  of  moths,  field  work. 

Rolla  P.  Currie,  in  charge  of  editorial  work. 

Mabel  Colcord,  librarian. 

ii 

58772°— 10 


CONTENTS. 


Page. 

Introduction 79 

Early  history 79 

Recent  records 80 

Distribution 80 

Food  plants 81 

Character  of  injury 81 

Description 82 

The  adult 82 

The  egg 82 

The  larva  and  larval  cases 83 

The  pupa 83 

Habits  of  the  adult 83 

Habits  of  the  larva 84 

Habits  of  the  pupating  larva 85 

Seasonal  history 85 

Recommendations 86 

Bibliography 86 


ILLUSTRATIONS. 


PLATES. 

Page. 

Plate  V.  Work  of  the  pecan  cigar  case-bearer  ( Coleophora  carysefoliella).  Fig. 

1. — Twig  of  pecan,  showing  injury  to  foliage.  Fig.  2. — Leaves  of 

pecan,  showing  mines 82 

VI.  Pecan  tree,  showing  foliage  checked  and  injured  by  pecan  cigar 

case-bearer 84 

VII.  Normal  pecan  tree,  same  size  as  that  shown  in  Plate  VI,  but  with- 
out injury  by  the  pecan  cigar  case-bearer 84 

TEXT  FIGURES. 

Fig.  23.  Pecan  twigs  with  buds  and  young  leaves  killed  by  pecan  cigar  case- 

bearer  ( Coleophora  carysefoliella) 81 

24.  The  pecan  cigar  case-bearer  {Coleophora  carysefoliella ):  Adult,  larvas  in 

cases 82 


iii 


r.  s.  D.  A.,B.  E.  Bui.  04,  Part  X. 


Issued  November  12,  1910. 


SOME  MISCELLANEOUS  RESULTS  OF  THE  WORK 
OF  THE  BUREAU  OF  ENTOMOLOGY— IX. 


THE  PECAN  CIGAR  CASE-BEARER. 

( Coleophora  carysefoliella  Clem.) 

By  H.  M.  Russell, 

Agent  and  Expert. 

INTRODUCTION. 

Among  the  insects  of  minor  importance  that  affect  the  pecan,  the 
pecan  cigar  case-bearer  (Coleophora  carysefoliella  Clem.)  is  probably 
met  with  in  groves  more  than  any  other  species.  At  times  the  insect 
occurs  in  such  numbers  as  to  defoliate  entire  trees,  checking  their 
growth  and  considerably  reducing  the  crop  of  nuts.  In  the  future 
this  insect  is  likely  to  cause  increasing  damage  as  the  acreage  in 
pecans  increases,  and  it  may  become  as  great  a pest  to  the  pecan  as 
Coleophora  fletcherella  Fernald  is  to  the  apple.  The  occurrence  of  this 
insect  in  large  numbers  at  Orlando,  Fla.,  during  the  spring  of  1909 
presented  the  opportunity  of  studying  it,  and  the  results  are  given 
in  this  article.  The  dates  for  appearance  of  the  different  stages  are 
for  that  locality.  These  dates  will  undoubtedly  vary  as  we  go  north-  - 
ward. 

EARLY  HISTORY. 

Clemens10  first  described  this  species  in  1861,  as  Coleophora  carysefo- 
liella,  from  larvae  found  feeding  in  their  cases  on  leaves  of  hickory 
during  the  fall.  He  gave  a short  description  of  the  larva  and  case, 
but  did  not  succeed  in  rearing  the  adult. 

In  1872  Clemens’s  original  description 2 was  republished  in  his 
“Tineina  of  North  America,”  edited  by  H.  T.  Stain  ton. 

Chambers,3  in  1874,  described  the  adult  under  the  name  Coleophora 
rufoluteella,  from  specimens  captured  in  Kentucky  in  June. 

Writing  again  in  1878,  Chambers4  places  his  rufoluteella  as  a 
synonym  under  carysefoliella.  He  wrote  at  that  time:  11 C,  rufoluteella 
Cham,  is  known  only  from  captured  specimens.  I am,  however, 
utterly  unable  to  distinguish  it  from  specimens  bred  by  me  in  the 
latter  part  of  June  from  larval  cases  found  feeding  on  hickory  leaves 

a The  numbers  in  superior  type  refer  to  corresponding  numbers  in  the  appended 
bibliography,  p.  86. 


79 


80 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU 


-IX. 


in  the  manner  described  by  Doctor  Clemens  for  carysefolieUa,  and  I 
believe  it  to  be  the  same  species.  ” 

Durino-  1882  Lord  Walsingham5  identified  a specimen,  reared  Irom 
Prunus  americana,  as  C.  rufoluteeUa  which  he  thought  to  be  distinct 
from  carysefolieUa.  Packard,'  in  1890,  wrote  -of  this  insect,  under 
insects  injurious  to  hickory:  “The  larva  feeds  in  a cylindrical  case 
attached  to  the  under  surface  of  the  leaves.  ” 

During  the  same  year  there  was  published  in  Insect  Life ' a brie 
note  recording  the  parasite,  RKyssalus  trilineatus  A shm  as  having 
been  reared  from  this  species  on  hickory  at  Washington,  D.  C.,  May 

r -I  009 

’ Apparently  nothing  more  was  written  until  1905,  when  Gossard,8 
in  his  bulletin  on  pecan  insects,  mentions  what  is  undoubtedly  this 
species  as  “ Coleophora  sp.” 

recent  records. 


Mav  5 1901,  Mr.  L.  O.  McPherson,  of  Josephine,  Ala.,  sent  in  larva; 
of  this  species  affecting  the  pecan.  Writing  of  this  attack  October  23 
1905  Mr  McPherson  stated  that  in  the  year  mentioned  this  insect 
entirely  denuded  a number  of  large  trees  of  their  leaves  during 

M June  3 W07,°the  larval  cases  of  this  insect  were  observed  on  pecan 
at’ Orlando,  Fla.  March  16,  1908,  the  winter  cases  of  these  larv* 
were  found  clustered  together  on  twigs  of  pecan  in  a deserted  gro\ 
outside  of  Orlando.  April  2 and  7,  1908,  the  larvae  were  again 
observed  at  Orlando,  Fla.  They  were  just  leaving  their  winter  cases 

f°Inh19oTSTpTand  May,  several  large  trees  in  the  grove  of 
Mr  C W Townsend,  of  Orlando,  Fla.,  were  almost  complete  y prt 
vented  from  putting  out  foliage  until  weeks  after  other  trees  had  done 
so,  because  the  larvae  of  this  species  were  so  numerous  on  the  buds 
and  leaves.  May  11  found  this  insect  causing  considerable  defolia- 
tion to  pecan  trees  at  the  old  Standard  Oil  grove  just  west  o Orlando 
now  owned  by  Mr.  Long.  At  the  same  time  it  was  abundant  m Ml 
the  groves  around  Orlando.  On  May  16  Mr.  J.  D.  Mitchell  of  this 
Bureau,  reared  this  insect  from  leaves  of  pecan  at  \ ic  ona,  ex. 


distribution. 


This  species  was  first  described  by  Clemens  in  a paper  on  North 
American  Tineina,  but  the  locality  for  his  specimens  is  not  given 
V T Chambers  records  it  from  larval  cases  taken  in  Kentucky  and 
records  capture  of  the  adult  at  Covington,  Ky.  Prof.  I.  A.  Gossan 
records  what  is  undoubtedly  this  species  as  met  with  on  almost 
every  tree  I examined  for  the  purpose  of  finding  it  mil  > • 

The  author,  while  working  in  Florida  during  the  years  1907  190J, 
found  it  in  every  grove  examined  around  Orlando. 


THE  PECAN  CIGAR  CASE-BEARER. 


81 


In  the  Bureau  of  Entomology  and  the  U.  S.  National  Museum  there 
are  specimens  from  McPherson,  Ala. ; Victoria,  Tex. ; Pittsburg,  Pa. ; 
Hampton,  N.  II. ; Washington,  D.  C. ; Virginia;  and  New  York. 

From  these  records  of  capture  and  injury,  this  insect  seems  to  be 
distributed  throughout  the  Austroriparian  faunal  area  of  the  United 
States  and  may  also 
extend  into  the  Caro- 
linian and  into  the 
lower  edge  of  the 
Alleghanian  areas. 


FOOD  PLANTS. 


The  pecan  cigar 
case-bearer  feeds 
principally  on  nut- 
bearing  trees,  and  of 
these  it  has  been  ob- 
served feeding  on 
walnut,  pecan,  and 
hickory.  It  has  been 
doubtfully  recorded 
on  dogwood  and 
Prunus  americana. 


CHARACTER  OF  IN- 
JURY. 


Damage  by  the  pe- 
can cigar  case-bearer 
occurs  during  the 
early  spring,  prin- 
cipally to  budded 
trees,  and  is  due  to 
the  feeding  of  the 
larvae  on  the  tender 
buds  and  unfolding 
leaves.  Where  this 
insect  is  very  abun- 
dant it  causes  injury 
in  two  ways.  If  the 
buds  are  backward  in  opening,  the  larvae  leave  the  twigs  where  they 
have  hibernated,  and  crawling  to  the  swelling  buds  attack  them  and 
eat  out  the  contents,  so  that  the  life  is  destroyed,  and  before  the  tree 
can  put  out  its  foliage  the  dormant  buds  must  develop.  Figure  23,  taken 
May  6,  1909,  shows  pecan  twigs  with  buds  destroyed  b\^  these  larvae; 


Fig.  23.— Pecan  twigs  with  buds  and  young  leaves  killed  by  pecan 
cigar  case-bearer  (Ooleophora  caryxfoliella).  (Original.) 


82 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


the  winter  cases  are  still  seen  attached  to  sides  of  the  buds.  On  the 
other  hand,  if  the  trees  develop  their  foliage  before  the  larvae  leave 
hibernation  in  injurious  numbers,  the  leaves  are  riddled  by  the  larvae 
as  they  come  from  the  twigs  and  the  wind  soon  whips  them  to  pieces. 
In  this  way,  by  feeding  on  the  opening  buds  and  young  leaves  in 
great  numbers,  this  insect  may  delay  the  trees  from  coming  into  foliage 
for  a period  of  from  six  to  eight  weeks.  Because  of  this,  young  trees 
are  held  back  during  the  most  important  period  of  their  growth,  and 
older  trees,  owing  to  this  extra  demand  for  nourishment  for  building 
leaves,  probably  have  the  crop  of  nuts  for  the  year  considerably 
decreased.  Plate  V,  figure  1,  shows  a pecan  twig  with  the  young 
leaves  ragged  and  largely  destroyed  by  this  insect,  and  Plate  V,  figure 
2,  shows  the  mines  of  the  larvse  and  some  of  the  case-bearers  at  work. 
Plate  VI  is  from  a photograph  of  a pecan  tree,  taken  May  6,  1909, 
showing  injury  by  this  insect.  Plate  VII  shows  a tree  not  attacked 

by  this  insect,  which  had  been  in  full 
foliage  for  at  least  four  weeks.  When 
the  writer  left  Orlando,  June  13,  the 
injured  tree  shown  in  Plate  VI  was  still 
partly  bare. 

DESCRIPTION. 

The  adult. — Coleophora  carysefoliella 
is  one  of  the  Microlepidoptera  belonging 

Fig.  24. — The  pecan  cigar  ease-bearer  (Coleo-  to  the  family  ElachistidsB,  characterized 
phora  caryxfoliella):  a,  Adult;  6,  c,  larvae  W narrow,  pointed  wingS  with  long 
incases.  Greatly  enlarged.  (Original.)  „ . ...  . rr,1  , . 

fringes  on  the  inner  margins.  1 he  adult 
is  a delicate  little  moth,  ochreous  in  color,  with  a wing  expanse  of  about 
9 mm.  The  head'  is  yellowish  ochreous,  with  white  scales  over  the 
eyes,  the  palpi  and  base  of  the  antennse  the  same  color  as  the  head, 
and  the  rest  of  the  antennae  white  ringed  with  brown.  The  body  is 
the  same  color  as  the  head,  while  the  fore  wings  are  reddish  ochreous 
with  costal  margin  white  and  fringe  on  inner  border  gray,' and  the 
hind  wings  are  gray  or  whitish.  This  moth  is  well  illustrated  in 
figure  24  at  a. 

Chambers  described  the  adult  as  follows: 


The  species  is  ochreous;  the  head  and  palpi  pale  or  yellowish  ochreous;  the  an- 
tennae white,  annulate  with  brown;  fore  wings  reddish  ochreous,  darker  towards  the 
apex,  with  the  costal  margin  from  base  to  cilia  white. 

The  ornamentation  of  the  imago  is  nearer  that  of  C.  limosipennella  than  to  any  of 
the  other  species  figured  in  Nat.  Hist.  Tin.  Al.  ex.  4£  lines. 

The  egg. — The  egg  has  not  been  observed  by  the  author,  but  is 
probably  very  similar  to  that  of  C.  jletcherella  as  described  by  A.  G. 
I laminar.® 


United  States  Dept.  Agr.,  Bur.  Ent.,  Bui.  80,  Pt.  II,  p.  37,  June  30,  1909. 


Bui.  64,  Part  X,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture. 


Plate  V. 


Fig.  1. — Twig  of  pecan,  showing  injury  to  foliage.  (Original.) 


Fig.  2. — Leaves  of  pecan,  showing  mines.  On  upper  leaf  are  larvae  in  cases  at  work.  About 
natural  size.  (Original.) 


Work  of  the  Pecan  Cigar  Case-bearer  (Coleophora  cary/efoliella). 


THE  PECAN  CIGAR  CASE-BEARER. 


83 


The  larva  and  larval  cases. — The  case  in  which  the  larva  passes  the 
winter  is  small,  3-3.5  mm.  long,  very  flat,  cylinderlike,  and  by  the 
end  of  winter  has  the  same  color  as  the  twigs  or  bark  on  which  it 
rests.  In  the  spring  the  larva  is  found  in  a case  that  is  considerably 
larger.  This  is  5-7  mm.  long,  cylindrical,  flattened  vertically  at  the 
upper  end,  and  slightly  rounded  at  the  lower.  This  case  is  made 
from  a hollowed  portion  of  leaf  and  so  shows  the  entire  leaf  structure. 
It  becomes  reddish  brown  in  color,  and  resembles  a minute  cigar. 

The  mature  larva  is  about  5.5  mm.  long  and  1 mm.  wide,  the 
cylindrical  body  having  well-marked  segments.  The  head  is  one- 
half  as  wide  as  the  body,  hemispherical,  flattened,  black  in  color, 
with  the  triangle  reddish.  The  body  is  light  brown,  with  cervical 
shield  oval,  shining  black,  divided  along  center  by  a light  brown  line. 
The  third  segment  of  the  body  has  a small  black  shield  like  the 
cervical,  the  anal  plate  shining  black.  The  surface  of  the  body  is 
finely  punctured  and  bears  scattered,  short,  white  hairs.  The  legs 
are  light  brown,  while  the  prolegs  are  wanting  or  very  small,  marked 
by  minute  elevations,  except  the  anal  pair,  which  are  large  and 
functional.  The  nearly  mature  larva  is  well  illustrated  in  its  case  in 
figure  24,  h,  c. 

The  pupa. — The  pupa  is  formed  within  the  larval  case,  and  is 
about  5.5  mm.  long  and  1 mm.  wide,  cylindrical,  having  nearly  the 
same  diameter  throughout  the  entire  length.  The  head  and  eyes  are 
blackish,  while  the  remainder  of  the  pupa  is  light  yellowish-brown. 
The  leg  cases  extend  beyond  the  tip  of  the  abdomen. 

Clemens  described  this  species  from  the  larval  case,  but  did  not 
rear  the  adult.  His  original  description  is  as  follows: 

1.  C.  carysefoliella.  The  larva  mines  the  leaves  of  hickory  in  September  and 
October.  The  head  and  body  is  [are]  reddish-brown,  somewhat  darker  on  the  second 
and  third  rings. 

The  case  is  small,  dark  brownish,  and  in  form  is  a flattened  simple  cylinder.  The 
larva  feeds  only  in  small  rectangular  patches,  of  which  there  are  usually  several  in 
the  same  leaf.  The  case  is  fixed  to  the  under  surface  and  the  larva  feeds  in  one  patch 
until  it  is  compelled  to  remove  its  entire  body  from  its  case,  and  then  removes  to 
another  part  of  the  leaf  to  form  a new  mine. 

HABITS  OF  THE  ADULT. 

The  moths  emerge  from  the  pupae  during  May  and  June  and  at  that 
time  may  be  found  among  the  pecan  trees.  When  only  recently 
emerged  from  the  pupae  they  rest  either  on  the  pupal  cases  or  on  the 
leaves  or  twigs  of  the  host  plant,  with  the  fore  wings  folded  back 
over  the  hind  wings  and  flat  over  the  abdomen,  while  the  antennae 
are  held  closely  together  and  directed  forward.  During  the  day  they 
seem  to  rest  among  the  leaves. 


84  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

HABITS  OF  THE  LARVA. 

The  larvae  of  Coleophora  caryxfoliella,  upon  hatching  from  the 
eggs  in  July,  mine  the  leaves  of  the  host  plant,  and  after  feeding  there 
for  some  time  cut  out  the  two  skins  of  the  mine  and  construct  the 
cases  within  which  they  live  during  the  fall  and  winter.  After  the 
cases  are  made  the  larvae  feed  upon  the  leaves  by  eating  through  the 
lower  epidermis  and  tunneling  out  the  interior  of  the  leaf  in  all 
directions  until  the  mine  is  so  large  that  to  mine  farther  the  larvae 
would  have  to  leave  their  cases.  Under  such  conditions  they  move 
and  begin  a new  mine,  so  that  the  leaves  become  full  of  irregular 
rectangular  patches  of  brown  with  a small  round  hole  in  the  center 
on  the  underside.  In  feeding,  the  larvae  carry  the  cases  nearly 
perpendicular  to  the  leaf  surface.  When  the  larvae  move  they  extend 
the  head  and  thorax  and  crawl  along,  bearing  the  case  aloft  behind. 
In  the  fall,  some  time  in  October,  before  the  leaves  fall,  these  larvae 
move  from  the  leaves  to  the  twigs  or  to  the  trunk,  where  they  get 
behind  the  bark.  Often  they  get  in  between  the  bud  and  the  twig. 
Here  they  fasten  the  cases  to  the  support  and  hibernate.  The  writer 
has  seen  from  fifteen  to  twenty  minute  cases  on  a twig  4 to  5 inches 
in  length,  and  where  very  abundant  they  will  cluster  together  literally 
in  hundreds.  Gossard 7 has  a photograph  of  these  winter  cases  com- 
pletely covering  a twig. 

In  the  spring,  when  the  weather  becomes  warm  enough,  generally 
between  March  15  and  April  1,  these  larvae  become  active  and  leave 
the  twigs,  where  they  have  spent  the  winter,  to  commence  feeding. 
If  the  trees  are  backward  they  often  begin  to  feed  before  the  leaves 
have  developed  and  in  such  cases  attach  themselves  to  the  swelling 
buds.  Each  larva  eats  a minute  round  hole  into  a bud  and  feeds  as 
long  as  it  can  reach  food  without  leaving  its  small  case.  When  this 
becomes  impossible  the  larva  changes  position  and  attacks  the  bud 
in  a new  place,  so  that  infested  buds  are  often  found  with  four  or 
five  holes  in  the  sides.  Under  such  treatment  the  buds  are  killed  or 
the  tiny  leaves  start  and  are  killed,  and  turning  brown  drop  off. 
Often  the  larvae  attack  the  young  tender  leaves  and  mine  out  rectan- 
gular blotches  in  them.  About  the  first  week  in  April  these  larvae 
outgrow  their  winter  cases  and  construct  larger  ones. 

Larvae  forming  new  cases  move  to  the  edge  of  the  leaf  and  mine 
between  the  two  skins.  They  then  cut  out  a portion  of  the  leaf, 
using  the  edge  for  one  side.  The  sides  are  then  sealed  with  silk,  an 
opening  being  left  at  one  end  for  the  head.  From  the  method  of 
making  new  nests  one  edge  of  the  case  will  often  show  serrations  of 
the  leaf  edge.  The  larvae  then  leave  the  old  case  attached  to  the 
leaf,  where  the  latter  has  been  cut  to  form  a new  case.  They  eat 
out  large  mines  from  2 to  8 mm.  long  and  4 to  5 mm.  wide  (PI.  V, 


Bui.  64,  PartX,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture. 


Plate  VI 


Pecan  Tree,  Showing  Foliage  Checked  and  Injury  by  Pecan  Cigar  Case-bearer. 

(Original.) 


Bui.  64,  Part  X,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture. 


Plate  VII, 


Normal  Pecan  Tree,  Same  Size  as  that  Shown  in  Plate  VI,  but  without  Injury 
by  the  Pecan  Cigar  Case-bearer.  (Original.) 


LIBRARY 

UNIVERSITY  OF  ILLINOIS 
UR6ANA 


THE  PECAN  CIGAR  CASE-BEARER. 


85 


fig.  2)  in  the  leaves,  feeding  generally  on  the  under  side  hut  some- 
times on  the  upper  also.  These  mines  are  deserted  by  the  larvae 
when  they  can  not  reach  more  of  the  surrounding  tissue  without 
leaving  their  cases,  and  new  mines  are  made.  In  this  way  badly 
infested  leaves  may  have  from  six  to  twenty  mines  to  each  leaflet. 
Soon  the  old  mines  dry  up  and  are  broken  out  by  the  wind,  leaving 
the  leaves  full  of  ragged  holes.  The  larvae  feed  during  the  day  and  can 
often  be  seen  with  the  head  and  part  of  the  body  inserted  between 
the  leaf  surfaces,  eating  out  the  tissues  in  an  ever-enlarging  angular 
mine.  If  disturbed  or  in  search  of  fresh  food,  these  larvae  will  move 
around  considerably.  When  making  a new  mine  the  end  of  the  case 
is  loosely  fastened  and  held  diagonally  attached,  to  the  leaf.  (See 
fig.  24.) 

HABITS  OF  THE  PUPATING  LARVA. 

During  May  most  of  the  larvae  become  mature  and  they  then 
either  fasten  the  case  tightly  to  the  leaves  and  pupate  or  move  to 
twigs,  branches,  or  bits  of  bark  on  the  trunk  of  the  tree  and  fasten 
the  cases  there.  The  larvae  spin  a quantity  of  silk  by  which  they 
fasten  the  cases  very  firmly  to  the  support,  after  which  they  reverse 
their  position,  so  that  the  head  is  pointing  out  toward  the  unattached 
end.  After  remaining  quiet  for  a number  of  days  the  pupae  are 
formed,  and  the  adults  emerge  during  the  last  of  May  or  the  first  of 
June. 

SEASONAL  HISTORY. 

As  far  as  observed,  this  insect  has  only  one  brood  during  the  year, 
the  larvae  hibernating  when  only  partially  grown. 

In  Florida  the  larvae  of  this  species  become  active  from  the  15th 
to  the  30th  of  March,  when  the  buds  of  the  pecan  are  opening,  or 
just  after  they  have  opened.  Leaving  the  twdgs  and  sheltered 
places  where  they  have  hibernated,  they  begin  feeding  on  the  buds 
or  tender  leaves.  In  a short  time  these  larvae  outgrow  their  old 
wflnter  cases  and  construct  new  ones  of  larger  size.  During  the  spring 
of  1908  this  occurred  mostly  between  April  1 and  April  7. 

The  larvae,  after  forming  new  cases,  continue  feeding  and  grovr 
rapidly  until  May,  when  they  become  full  grown. 

By  May  4,  1909,  a few  larvae  pupated  and,  as  others  pupated  from 
time  to  time,  by  May  19  or  20  the  greater  part  of  the  brood  was  in 
the  pupal  state.  This  pupal  period  occupies  about  twelve  days. 

An  adult  was  observed  in  the  cage  on  May  11,  but  most  of  the 
moths  emerge  from  May  27  to  June  5.  On  June  3 the  adults  were 
abundant  on  the  foliage  of  pecan. 

The  adult  probably  lays  her  eggs  on  the  underside  of  the  leaves 
during  June,  and  by  the  middle  of  July  the  larvae  are  working  as 
miners  in  the  leaves  of  pecan.  After  a time  they  construct  their 


86 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


minute  cases  and  feed  on  the  foliage  until  fall,  probably  until  the! 
last  of  September  or  first  part  of  October,  when  they  move  to  twigs  to 
hibernate,  sometimes  being  packed  around  them  by  the  hundreds. 
Others  hibernate  under  bits  of  bark  on  the  trees  or  in  crotches  and 
other  sheltered  spots. 

RECOMMENDATIONS. 

Where  this  insect  becomes  abundant  enough  to  be  injurious  it 
can  with  little  doubt  be  controlled  by  spraying  the  trees  with 
arsenate  of  lead  (at  the  rate  of  3 pounds  to  50  gallons  of  water) 
when  the  buds  are  swelling — in  March  in  central  Florida  and  in 
similar  climates.  When  the  larvae  attack  the  foliage,  this  should  be 
similarly  sprayed. 

Lime-sulphur  mixture  applied  during  the  dormant  season  would 
undoubtedly  give  good  results. 

Where  trees  are  sprayed  in  spring  for  the  budworm  ( Proteopteryx 
deludana  Clem.)  no  further  treatment  will  be  required  for  the  case- 
bearer. 

A bibliographical  list  follows: 

BIBLIOGRAPHY. 

1.  Clemens,  Brackenridge. — Proceedings  of  the  Entomological  Society  of  Phila- 

delphia, Yol.  I,  p.  78,  1861. 

Original  description  of  the  species  from  larva  and  case;  adult  not  reared. 

2.  Clemens,  Brackenridge. — Tineina  of  North  America,  p.  166,  1872.  Edited 

by  H.  T.  Stainton. 

Same  account  as  in  No.  1. 

3.  Chambers,  Y.  T. — Canadian  Entomologist,  Vol.  VI,  p.  129,  1874. 

Described  captured  adults  as  C.  rufoluteella  n.  sp. 

4.  Chambers,  V.  T. — Canadian  Entomologist,  Vol.  X,  p.  112,  1878. 

Made  his  rufoluteella  synonym  of  carysefoliella,  giving  description  of  adult,  larva,  and  larval  case, 
and  brief  account  of  larval  habits. 

5.  Walsingham,  Thos. — Transactions  of  the  Entomological  Society  of  London  for 

1882,  pp.  430-431. 

Regards  rufoluteella  as  distinct  from  carysefoliella. 

6.  Packard,  A.  S. — Fifth  Report  U.  S.  Entomological  Commission,  p.  316,  1890. 

A brief  account  of  habits. 

7.  [Editorial], — Insect  Life,  Vol.  II,  p.  351,  1890. 

Mention  of  parasite. 

8.  Gossard,  H.  A. — Bui.  79,  Florida  Agricultural  Experiment  Station,  p.  304,  1905. 

Brief  account  of  injury  to  pecan  by  an  unidentified  Coleophora,  probably  this  species,  and 

remedies.  . 1 

Brief  mention  has  also  been  made  of  the  occurrence  of  this  species 
in  Florida  and  Texas  in  recent  Yearbooks  of  the  Department. 


o 


INDEX. 


! 

I 


Page. 

| Adeliopria  longii,  parasite  of  Ceratopogon  wheeleri 28 

brides,  food  plants  of  Heliothrips  haemorrhoidalis 51 

Msculus  hippocastanum , habitat  of  Ceratopogon  hippocastani 28 

Agricultural  conditions  at  Barstow,  Tex 2 

Agromyza  aeneiventris  taken  on  loco  weed  (Aragallus),  clover,  Ambrosia,  and 

peas 41 

Aleyrodes  citri,  enemy  of  citrus  in  Florida 65 

howardi 65-71 

adult,  description 70 

description 68-70 

distribution 70 

egg,  description 68 

enemies,  natural 70-71 

food  plants 70 

injury  and  extent  of  infestation 65-66 

introduction 65 

larva,  first  instar,  description 69 

second  instar,  description 69 

third  instar,  description 69 

life  history 66-68 

pupa,  description 69-70 

remedies 71 

nubifera,  enemy  of  citrus  in  Florida 65 

Alfalfa,  avoidance  of  injury  to  seed  crop  by  conchuela 12 

damage  by  Pentatoma  ligata  and  P.  sayi  in  1905 3-5 

previous  to  1905 3 

food  plant  of  Aphis  medicaginis 40 

Pentatoma  ligata 3-5 

sayi 2,  3 

protection  from  attacks  of  conchuela  and  grain  bug 12-14 

Alligator  pear.  (See  Persea  gratissima.) 

Alydus  eurinus  on  Lima  beans  and  cowpeas 41 

taken  on  loco  weeds 41 

pluto  taken  on  loco  weeds 41 

Amaranthus,  food  plant  of  Hadronotus  militaris 41 

Ambrosia,  food  plant  of  Agromyza  aeneiventris 41 

Amorpha  fruticosa,  food  plant  of  Walshia  amorphella 34 

Anopheles  barberi,  location  of  larvae 24-25 

Ant,  notes  on  a Colorado  Bpecies 73-78 

Ants  on  loco  weeds. 40 

Aphicide  against  greenhouse  thrips 53-54 

Aphides  attended  by  Formica  cinereorufibarbis 73-74 

Aphiochaeta  pygmxa  on  Astragalus  mollissimus 42 

Aphis,  bur-clover.  (See  Aphis  medicaginis .) 
cotton.  (See  Aphis  gossypii.) 

68045°— Bull.  64—11 3 87 


88  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

Page. 

Aphis  gossypii  on  cucurbits,  attendance  by  Formica  cinereorufibarbis 73-74 

medicaginis  on  loco  weeds 40 

prey  of  Hippodamia  convergens 40 

melon.  (See  Aphis  gossypii.) 

punk  against  greenhouse  thrips 54 

Apion  seneipenne  on  Meibomia  (Desmodium) 31 

colon  on  wild  bean  in  Mexico 30 

cribricolle  on  Lotus  glabra 31 

decoloratum  on  Meibomia  paniculata  and  M.  granaiflora,  parasite 31-32 

fraternum,  synonym  of  Apion  griseum 30 

griseum,  food  plants  and  habits,  parasite 29-30 

herculanum,  food  plants 32 

injurious  North  American  species,  with  notes  on  related  forms 29-32 

nigrum  on  locust 31 

patruele  on  wild  legume 31 

proclive  on  Lupinus  arborea,  parasite 31 

segnipes  on  Cracca  virginwma , parasite 31 

turbulentum  on  Meibomia  marylandica 31 

Apple,  food  plant  of  Coleophora  fietcherella 79 

Heliothrips  hsemorrhoidalis 44 

Apples,  food  of  Euxesta  notata 39 

Ar secerns  fasciculatus 61-64 

habits  in  general 64 

in  chinaberries 63-64 

injury  to  corn 61-62 

introduction 61 

life  history  in  com 63 

parasites 63-64 

Aragallus  lamberti,  food  plant  of  Aphis  medicaginis 40 

Cleonus  quadrilineatus 37 

Melanoplus  spp 42 

(Ecanthus  sp 42 

Opeia  obscura 42 

Parabacillus  coloradus 42 

Tritoxa  incwrva 38 

hymenopterous  gall  thereon 41 

Armadillidium  vulgare,  biological  notes 19-21 

color  differences  between  sexes 19-20 

copulation 19 

effect  of  varying  natural  and  field  conditions 19 

habits - 15-21 

haunts 19 

incubation  period 20 

life  history 15-21 

molts 20-21 

plant-feeding  habits 18-19 

regeneration  of  parts 21 

remedies 21 

scavenger  habits 19 

sexual  differences 19-20 

Arsenate  of  lead  against  pecan  cigar  case-bearer 86 

Arsenic  against  sowbug  Armadillidium  vulgare • 17, 18 

Arsenicals  against  sowbug  Metoponorthus  pruinosus 22 


INDEX. 


89 


Page. 

Arsenicals  against  sowbugs 22 

Aschersonia  aleyrodis,  fungous  enemy  of  Aleyrodes  howardi 70-71 

flavocitrina 68 

Asopia  costalis.  (See  Hypsopygia  costalis.) 

Aspidium,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Astragalus  mollissimus,  (see  also  Loco,  purple). 

food  plant  of  Aphiochxta  pygmxa 42 

Aphis  medicaginis 40 

Bruchus  aureolus 41 

Euxesta  notata 38-39 

Pegomya  lupini 35-36 

Rusticus  acmon 42 

unknown  leaf-beetle 41 

Walshia  amorphella 34-35 

roots,  food  of  Pyralis  farinalis 40 

i Azalea,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

| Back,  E.  A.,  paper,  “The  Woolly  White-fly:  A New  Enemy  of  the  Florida 

I Orange.  (Aleyrodes  howardi  Quaintance)” 65-71 

Bacon  eaten  by  Armadillidium  vulgare 17 

Baris  transversa  on  cocklebur. 39 

Bean,  Metcalfe.  (See  Phaseolus  retusus .) 

‘ ‘ Raphael . ’ ’ (See  Phaseolus  wrightii.) 

wild,  food  plant  of  Apion  colon 30 

Beans,  damage  by  Pentatoma  ligata  in  1905 7-8 

dried,  food  of  Arxcerus  fasciculatus 64 

injury  by  Armadillidium  vulgare 16 

Lima,  food  plant  of  Alydus  eurinus 41 

Pentatoma  sayi 2 

Beetle  of  unknown  species  on  Astragalus  mollissimus 41 

Beets,  food  plants  of  Hadronotus  militaris 41 

sugar,  food  plant  of  Euxesta  notata 39 

Begonia,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Bird  enemies  of  Pentatoma  ligata 11 

“Black  fly,”  name  given  to  Heliothrips  hxmorrhoidalis  in  Germany 44 

hibernation  in  holes  made  by  Arxcerus  jasciculatus  in  cornstalks.  61-62 

Boll  weevil,  host  of  Cerambycobius  cushmani 63-64 

Eurytoma  tylodermatis 64 

Boophilus  annulatus,  eggs  eaten  by  Armadillidium  vulgare 17 

Porcellio  Ixvis 22 

Bread  eaten  by  Armadillidium  vulgare 17 

Bruchomorpha  dorsata  taken  on  loco  weeds 41 

Bruchus  aureolus  on  loco  weed  (Astragalus) 41 

obsoletus  on  Cracca  virginiana 41 

Budworm,  pecan.  (See  Proteopteryx  deludana.) 

Bug,  green  tree.  (See  Nezara  hilaris .) 

Buhach.  (See  Pyre  thrum.) 

Burning  against  chinch  bug 14 

conchuela 13-14 

Cabbage,  food  plant  of  Euxesta  notata 39 

Cacao,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Camarotes,  food  plants  of  Heliothrips  hxmorrhoidalis 51 

Canteloupes,  crushed  overripe,  food  of  Formica  cinereorufibarbis 73 

food  plants  of  Aphis  gossypii 73-74 


90 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU — IX. 


Page. 

Caragana  arborescens,  food  plant  of  Aphis  medicaginis 40 

Carbon  bisulphide  against  sowbugs  in  greenhouses  and  dwellings 21,  22 

too  expensive  for  use  against  ant  Formica  drier eorufibarb is . . 74 

Cassia,  food  plant  of  Aphis  medicaginis 40 

Catolaccus  incertus,  parasite  of  Apion  decoloratum.. . , 32 

griseum 30 

Cattleya,  food  plants  of  Eeliothrips  hxmorrhoidalis 51 

Cerambycobius  cushmani,  parasite  of  Arxcerus  fasciculatus 63-64 

boll  weevil 63-64 

Ceratopogon  braueri,  a myrmecophile 27 

brumalis , habits,  distribution 27 

cinctus,  biting  habits,  distribution 26 

griseus,  habits,  distribution 27 

guttipennis,  biting  habits 23-24 

larva,  habits  and  description 24-25 

hippocastani , habits 28 

mutabilis  reared  from  human  excrement,  distribution 27 

sanguisuga,  biting  habits,  distribution 26 

spp.,  notes 23-28 

specularis,  habits,  distribution 27 

stellifer , biting  habits,  distribution 26 

stenammatis,  association  with  Stenamma  fulvum  aquia 27 

texanus,  habits,  distribution 28 

unicolor , biting  habits,  distribution 26 

varicolor,  pupa 25 

varipennis,  biting  habits,  distribution 26 

websteri,  habitat 27 

wheeled , habits,  distribution 28 

Chaitophorus  populicola  on  cottonwood,  attendance  by  Formica  cinereorufibarbis . 73 

Chalcidid  parasite  of  Apion  proclive 31 

Cherry  laurel,  food  plant  of  Eeliothrips  hxmorrhoidalis 51 

Chinaberry.  (See  Melia  azedarach.) 

Chinch  bug,  burning  in  control 14 

Chittenden,  F.  H.,  paper,  “An  Injurious  North  American  Species  of  Apion, 

with  Notes  on  Related  Forms” 29-32 

“Insects  Injurious  to  the  Loco  Weeds” 33-42 

Chrysopa  carried  away  from  aphis-infested  cucurbit  plants  by  Formica  cine- 
reorufibarbis  74 

Citrus,  food  plants  of  Aleyrodes  howardi 70 

Cleonus  quadrilineatus,  injurious  to  loco  weeds,  general  account 37-38 

Clover,  bur,  food  plant  of  Aphis  medicaginis 40 

food  plant  of  Agromyza  xneiventris 41 

Aphis  medicaginis 40 

hay  worm.  (See  Eypsopygia  costalis.) 

Cocklebur,  food  plant  of  Baris  transversa 39 

Euxesta  notata 39 

Coffee  bean.  ( See  Cassia.) 

weevil.  (See  Arxcerus  fasdculatus.) 

Colcophora  caryxfoliella 79-86 

adult,  description 82 

habits 83 

bibliography 86 

control  recommendations 86 


INDEX. 


91 


Tage. 

Coleophora  caryxfoliella,  description 82-83 

distribution 80-81 

early  history 79-80 

egg 82 

food  plants 81 

habits  83-85 

injury,  character 81-82 

introduction 79 

larva,  description 83 

habits 84 

larval  cases,  description 83 

pupa,  description 83 

pupating  larva,  habits 85 

recent  records 80 

seasonal  history 85-86 

fletcherella  on  apple 79 

rufoluteella,  bibliographic  reference 86 

= Coleophora  carysefoliella 79 

Conchuela.  (See  Pentatoma  ligata.) 

Corn,  food  plant  of  Ar secerns  fasciculatus 61-63 

Euxesta  notata 39 

Pentatoma  ligata 8 

Cornus  sp.  ( See  Dogwood.) 

Cotton  aphis.  (See  Aphis  gossypii .) 

bolls,  dry,  decayed,  food  of  Arxcerus  fasciculatus 64 

boll  weevil.  ( See  Boll  weevil.) 

damage  by  Pentatoma  ligata  in  Texas  in  1905 6 

previous  to  1905 2-3 

food  plant  of  Aphis  medicaginis 40 

cotton  aphis 40 

Euxesta  notata 39 

Pentatoma  ligata 6 

injury  by  Armadillidium  vulgare 16 

leaves  fed  upon  by'  Metoponorihus  pruinosus 22 

Porcellio  Ixvis 21 

Cottonwood,  food  plant  of  Chaitophorus  populicola 73 

Cowpea,  food  plant  of  Alydus  eurinus 41 

Aphis  medicaginis 40 

Nezara  hilar  is 8 

Cracca  virginiana,  food  plant  of  Apion  segnipes 31 

Bruchus  obsoletus 41 

Crinums,  food  plants  of  Heliothrips  hxmorrhoidalis 51 

Crotons,  food  plants  of  Heliothrips  hxmorrhoidalis 43, 44-45,  51 

Crow,  enemy  of  pentatomid  bugs 11 

Cucumbers,  injury  by  Armadillidium  vulgare 16 

Cucurbits,  food  plants  of  Aphis  gossypii 73 

Culex  signifer , location  of  larvae 24-25 

triseriatus,  location  of  larvae 24-25 

Dahlias,  food  plants  of  Heliothrips  hxmorrhoidalis 51 

Dasycoris  humilis  taken  on  loco  weeds 41 

Date  palm,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

palms,  injury  by  Armadillidium  vulgare 16 


92 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU — IX. 


Pagel 

Deltocephalus  Jlexulosus  taken  on  loco  weeds 41 

Dendrobium,  food  plants  of  Heliothrips  haemorrhoidalis 51 

Desmodium.  ( See  Meibomia.) 

Disease  transmission  possible  by  sowbugs 15,  22 

Dogwood,  doubtful  food  plant  of  Coleophora  caryaefoliella 81 

food  plant  of  Apion  herculanum 32 

Eciton  caecum,  nests  containing  larvae  and  puparia  of  Ceratopogon  brumalis . . 27 

Eel- worms.  ( See  Nematodes.) 

Eucharis,  food  plants  of  Heliothrips  haemorrhoidalis 51 

Eurytoma  tylodermatis,  parasite  of  Apion  segnipes 31 

Ar  secerns  fasciculatus 64 

boll  weevil 64 

Tyloderma  foveolatum 31 

Euxesta  notata  on  loco  weed,  general  account 38-39 

Excrement,  human,  Ceratopogon  griseus  reared  therefrom 27 

mutahilis  reared  therefrom 27 

Euxesta  notata  reared  therefrom 39 

False-indigo  gall-moth.  (See  Walshia  amorphella.) 

Farm  practices  of  little  avail  against  conchuela  in  western  Texas 11-12 

Ferns,  food  plants  of  Heliothrips  haemorrhoidalis 51 

Ficus,  food  plants  of  Heliothrips  haemorrhoidalis 51 

Fire.  ( See  Burning.) 

Flour  eaten  by  Armadillidium  vulgar e 17 

Flowers,  cultivated,  injury  by  Armadillidium  vulgar e 16 

Flower  seed  subject  to  attacks  by  Armadillidium  vulgare 16 

Forage  plants,  injury  by  Apion  griseum 29 

Formica  cinereorufibarbis 73-78 

attendance  on  aphides 73-74 

injurious  habits 73-74 

introduction 73 

potassium  cyanide  as  remedy,  experiments. . . : 74-78 

Fruits,  dried,  food  of  Araecerus  fasciculatus 64 

Fuchsia,  food  plant  of  Heliothrips  haemorrhoidalis 51 

Fumigation  against  woolly  white-fly 71 

experiments  against  greenhouse  thrips 52-56 

of  peach  trees  against  conchuela  and  related  pests 14 

treatments  recommended  against  greenhouse  thrips 57-58 

Fungous  growths,  food  of  Armadillidium  vulgare 17 

Fungus  gnats.  ( See  Mycetophilidse.) 

growing  on  honeydew  excreted  by  Aleyrodes  howardi 68 

Fungus,  red.  (See  Aschersonia  aleyrodis .) 

yellow  white-fly.  (See  Aschersonia  fiavodtrina.) 

Gall,  hymenopterous,  on  Aragallus  lamberti 41 

moth,  false-indigo.  (See  Walshia  amorphella.) 

Garden  vegetables,  damage  by  Pentatoma  ligata  in  1905 7-8 

protection  from  attacks  of  conchuela  and  related  pests 14 

Geocoris  griseus  taken  on  loco  weeds 41 

Glycyrrhiza  lepidota,  food  plant  of  Aphis  medicaginis 40 

Gnats,  biting.  (See  Ceratopogon  spp.) 

fungus.  ( See  Mycetophilidae.) 

Goat’s  rue.  (See  Cracca  virginiana.) 

Grain  bug.  (See  Pentatoma  sayi.) 

stored,  food  of  Pyralis  farinalis 40 


INDEX. 


93 


Page, 

Grape,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Grapes,  damage  by  Pentatoma  ligata  in  1905 7 

protection  from  attacks  of  conchuela  and  related  pests 14 

Grasses,  probable  food  plants  of  Philxnus  bilineatus 41 

Grass,  eaten  by  Armadillidium  vulgar e 18-19 

Grasshoppers  and  other  Orthoptera  on  loco  weed,  Aragallus  lamberti 42' 

Greenhouses,  infestation  by  Sciara  inconstans 36-37 

Guava,  food  plant  of  Aleyrodes  howardi 70 

Gymnosoma  fuliginosa,  parasite  of  Pentatoma  ligata 11 

Eadronema  militaris  on  Amaranthus  and  beets 41 

taken  on  loco  weeds 41 

Hand  picking  against  conchuela,  grain-bug,  and  related  pests 13, 14 

Hay,  clover,  food  of  Pyralis  farinalis 40 

Heliothrips  adonidum , bibliographic  reference 58 

hxmorrhoidalis 43-60* 

adult,  description 46-47 

habits 48-49 

bibliography 58-60 

control,  artificial 52-58 

natural 52 

description 46-48 

distribution ? 45-46 

egg,  description 47 

food  plants 51 

generations 52 

habits 48-51 

history 43-44 

injury,  nature  and  extent 44-45 

introduction 49 

larvae,  habits 49-50 

larva,  first  stage,  description 47 

second  stage,  description 47 

life  cycle 51 

history 51-52 

longevity 51 

natural  enemies 52 

nymph,  full-grown,  or  pupa,  description 48 

young,  or  prepupa,  description 47-48 

origin 45 

prepupa,  description 47-48 

habits 50 

pupa,  description 48 

habits 51 

records,  recent 44 

remedies,  experiments 52-57 

summary 57 

recommended 57-58 

Hickory,  food  plant  of  Coleophora  caryxfoliella 79,  80,  81 

Hippodamia  convergens  carried  away  from  aphis-infested  plants  by  Formica 

cinereorufibarbis 74 

enemy  of  Aphis  medicaginis 49 

Honeysuckle,  food  of  Armadillidium  vulgare 18-19 


94 


MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 


Page. 

Hopperdozer  for  use  against  conchuela  and  grain-bug 12-13 

Horsechestnut.  (See  JEsculus  hippocastanum.) 

HosacJcia  glabra.  (See  Lotus  glabra.) 

Hothouse  vegetables,  injury  by  Armadillidium  vulgar e 16 

Hydrocyanic-acid  gas  against  greenhouse  thrips 56, 58 

Bypsopygia  costalis  breeding  in  clover  hay 40 

Indigo,  false.  (See  Amorpha  fruticosa.) 

Insects  injurious  to  loco  weeds 33-42 

Jarring  against  conchuela  and  related  pests 14 

Kerosene  against  sowbug  Armadillidium  vulgar e 18 

emulsion  against  conchuela,  grain-bug,  and  related  pests 13, 14 

greenhouse  thrips 58 

sowbug  Armadillidium  vulgar e 18 

Kola,  food  plant  of  Heliotkrips  hxmorrhoidalis 51 

Ladybird,  convergent.  (See  Hippodamia  convergens.) 

Lxlaps  macropilis,  enemy  of  Heliothrips  hxmorrhoidalis . . 52 

Laelia,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Laurel,  cherry.  ( See  Cherry  laurel.) 

Laurestina,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Lefortia,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Legume,  wild,  climbing,  food  plant  of  Apion  patruele 31 

Lettuce  subject  to  attacks  by  Armadillidium  vulgar e 16 

Liliaceous  plants,  food  plants  of  Heliothrips  hxmorrhoidalis , 51 

Lime-sulphur  mixture  against  pecan  cigar  case-bearer 86 

Loco  fly,  yellow.  (See  Tritoxa  incurva.) 

purple  (see  also  Astragalus  mollissimus) . 

food  plant  of  Sciara  inconstans ) 36 

root-maggot.  (See  Pegomya  lupini.) 

weeds  (see  also  Astragalus  molissimus  and  Aragallus  lamberti). 

insect  enemies 33-42 

white.  (See  Aragallus  lamberti.) 

weevil,  four-lined.  (See  Cleonus  quadrilineatus.) 

woolly.  ( See  Loco,  purple,  and  Astragalus  mollissimus.) 

Locust,  food  plant  of  Apion  nigrum 31 

London  purple  against  sowbug  Armadillidium  vulgare 17, 18,  21 

Lotus  glabra , food  plant  of  Apion  cribricolle 31 

Lupinus  alba,  food  plant  of  Pegomya  lupini 36 

arborea,  food  plant  of  Apion  proclive 31 

Pegomya  lupini 36 

Walshia  amorphella 35 

Lycxna  acmon.  (See  Rusticus  acmon.) 

Mangifera  indica.  (See  Mango.) 

Mango,  food  plant  of  Aleyrodes  howardi 70 

Heliothrips  hxmorrhoidalis 44, 51 

Manure,  cow,  Ceratopogon  specularis  reared  therefrom 27 

horse,  Ceratopogon  specularis  reared  therefrom 27 

Maples,  food  plants  of  Heliothrips  hxmorrhoidalis 51 

Marcintacia,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Marsh,  II . O. , paper,  ‘ ‘Notes on  a Colorado  Ant  ( Formica  dnereorufibarbis  Forel)”  73-78 
Meal  snout-moth.  (See  Pyralis  farinalis.) 

Meibomia,  food  plant  of  Apion  xneipenne 31 

grandijlora,  food  plant  of  Apion  dccoloratum 31 

rnarylaridica,  food  plant  of  Apion  turbulentum 31 


INDEX. 


95 


Page. 

Meibomia  paniculata,  food  plant  of  Apion  decolor atum 31 

Melanoplus  spp.  on  Aragallus  lamberti 42 

Melia  azedarach , food  plant  of  Arxcerus  fasciculatus 63-64 

Mclilotus  italica , food  plant  of  Aphis  medicaginis 40 

Melon  aphis.  (See  Aphis  gossypii.) 

Mesquite,  food  plant  of  Pentatoma  ligata 8 

Metoponorthus  pruinosus,  life  history  and  habits,  notes 22 

Midge,  fickle.  (See  Sciara  inconstans.) 

Milo  maize,  damage  by  Pentatoma  ligata  and  P.  sayi  in  1905 5-6 

food  plant  of  Pentatoma  sayi 2 

protection  from  attacks  of  conchuela  and  related  pests 14 

Morrill,  A.  W.,  paper,  “The  Mexican  Conchuela  in  Western  Texas  in  1905 

(Pentatoma  ligata  Say)  ” 1-14 

Mushrooms,  injury  by  Armadillidium  vulgare 16 

Mustard  subject  to  attacks  by  Armadillidium  vulgare 16 

Mycetophilidse,  habits  of  family 36 

Nabis  ferus  taken  on  loco  weeds ' 41 

Nematodes,  confusion  of  larvse  of  Sciara  inconstans  therewith 37 

Nezara  hilaris,  damage  to  cowpea  vines  and  tomatoes 8 

Nico-fume  liquid  against  greenhouse  thrips 55 

paper  against  greenhouse  thrips 52-53 

Nicotine  liquids  for  spraying  against  greenhouse  thrips 57-58 

papers  for  fumigation  against  greenhouse  thrips 57 

Oats,  food  plant  of  Pentatoma  sayi 2 

CEcacta  furens,  biting  habits,  distribution 28 

(Ecanthus  sp.  on  Aragallus  lamberti 42 

Onion  fly,  black.  (See  Tritoxa  fiexa.) 

food  plant  of  Euxesta  notata 39 

Tritoxa  fiexa 38-39 

Opeia  obscura  on  Aragallus  lamberti 42 

Orange,  Aleyrodes  howardi  a new  enemy  in  Florida 65-71 

Osage  orange,  food  plant  of  Euxesta  notata 39 

Oxalis,  food  plant  of  Aphis  medicaginis 40 

Palmetto,  injury  by  Armadillidium  vulgare 16 

Palms,  food  plants  of  Heliothrips  hxmorrhoidalis 51 

Pancratium,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Parabacillus  coloradus  on  Aragallus  lamberti 42 

Paraleyrodes  per  sex 65 

Paris  green  against  sowbug  Armadillidium  vulgare 17, 18, 21 

and  lime  against  sowbug  Armadillidium  vulgare 18 

Peaches,  damage  by  Pentatoma  ligata  in  1905 6-7 

protection  against  attacks  of  conchuela  and  related  pests 14 

Peas,  damage  by  Pentatoma  ligata  in  1905 7-8 

food  plant  of  Agromyza  xneiventris 41 

Pentatoma  ligata 7-8 

sayi 2 

injury  by  Armadillidium  vulgare 16 

Pecan  budworn.  (See  Proteopteryx  deludana.) 

cigar  case-bearer.  (See  Coleophora  caryxfoliella .) 

food  plant  of  Coleophora  caryxfoliella 79-86 

Pediculoides,  enemy  of  Arxcerus  fasciculatus 64 

Pegomya  lupini  injurious  to  loco  weed,  general  account 35-36 

Pellea  hastata,  food  of  Heliothrips  hxmorrhoidalis 51 


96  MISCELLANEOUS  RESULTS  OF  WORK  OF  BUREAU IX. 

Page. 

Peppers,  food  plants  of  Pentatoma  ligata 8 

Persea  gratissima,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Persimmon  Psylla.  ( See  Psylla,  persimmon.) 

Pentatoma  ligata 1-14 

an  associated  species 2 

and  P.  sayi,  remedies  when  crops  other  than  alfalfa  are  at- 
tacked  14 

control  methods 11-14 

damage  to  crops  in  1905 3-8 

previous  to  1905 2-3 

egg  parasites 9-10 

food  plants 3-8 

host  of  Telenomus  ashmeadi 10 

introduction 1 

natural  enemies 9-11 

predaceous  enemies 11 

preventive  and  protective  measures 13-14 

seasonal  history 8-9 

tachinid  parasites 11 

sayi,  association  with  Pentatoma  ligata  in  injury  to  crops 2 

control  measures 12-14 

damage  to  alfalfa  in  1905 3-5 

previous  to  1905 3 

milo  maize  in  1905 6 

seasonal  history 8-9 

Phalenopsis,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Phaseolus  paucijlora.  (See  Strophostyles  paucifiora.) 

polystachyus  ( perennis ),  food  plant  of  Apian  griseum 29 

retusus,  food  plant  of  Apion  griseum 29 

wrightii,  food  plant  of  Apion  griseum 29 

Philsenus  hilineatus  taken  on  loco  weeds 41 

Phlox,  food  plant  of  Heliothrips  haemorrhoidalis 51 

Pierce,  W.  Dwight,  paper,  “Notes  on  the  Economic  Importance  of  Sowbugs”. . 14-22 

* ‘ Pill-bug.’ ’ (See  Armadillidium  vulgar e.) 

Pink,  food  plant  of  Heliothrips  hxmorrhoidalis 51 

Plant-lice.  ( See  Aphides.) 

Porcellio  Ixvis,  life  history  and  habits,  notes 21-22 

remedies 22 

Potassium  cyanide  solution  against  Formica  cinereorufibarhis 74-78 

Potatoes  eaten  by  Armadillidium  vulgare 17 

Potted  plants  subject  to  attacks  by  Armadillidium  vulgare 16 

Pratt,  F.  C.,  paper,  “Notes  on  ‘Punkies’  ( Ceratopogon  spp.)” 23-28 

Prionocyphon  discoideus,  location  of  larvae 24-25 

Prodenia  ornithogalli 17 

Proteopteryx  deludana,  spraying  therefor  will  destroy  pecan  cigar  case-bearer. . . 86 

Prunus  americana,  doubtful  food  plant  of  Coleophora  rufoluteella  (caryxfoliella) . . 80,  81 

Psylla,  persimmon 68 

“Punkios.”  (See  Ceratopogon  spp.) 

Pyralis  farinalis  on  Astragalus  mollissimus 40 

Pyrethrum  against  sowbug  Armadillidium  vulgare 17, 18 

fumigation  therewith  against  conchuela  on  peach  trees 14 

Radishes  eaten  by  Armadillidium  vulgare 16, 17 

Rain,  factor  in  control  of  Heliothrips  hxmorrhoidalis 52 


INDEX. 


97 


Pago. 

Reduviolus  ferus,  carried  away  from  aphis-infested  cucurbit  plants  by  Formica 

cinereorufibarbis 74 

Regeneration  of  parts  in  Armadillidium  vulgare 21 

Repellents  against  sowbug  Armadillidium  vulgare 18 

Rhyssalus  irilineatus,  parasite  of  Colephora  carysefoliella 80 

Robinia  viscosa , food  plant  of  Aphis  medicaginis 40 

Root  fly,  spotted.  (See  Euxesta  notata.) 
maggot,  loco.  (See  Pegomya  lupini.) 

Rose,  injury  by  Armadillidium  vulgare 16 

leaf  insecticide,  fumigation  against  greenhouse  thrips 55 

spraying  against  greenhouse  thrips 56 

Russell.  H.  M.,  paper,  ‘‘The  Greenhouse  Thrips  ( Heliothrips  hsemorrhoidalis 

Bouch6)” 43-60 

“The  Pecan  Cigar  Case-bearer  ( Coleophora  carysefoliella 

Clem.)  ” 79-86 

Rusticus  acmon  on  Astragalus  mollissimus 42 

Sciara  inconstans  injurious  to  purple  loco,  general  account 36-37 

Screening  tomatoes  against  conchuela 14 

Sheepberry.  (See  Viburnum  lentago.) 

Snout-moth,  meal.  (See  Pyralis  farinalis.) 

Soapsuds  against  greenhouse  thrips 43 

Solanum,  food  plant  of  Euxesta  notata 39 

Sowbugs,  economic  importance 15-22 

conclusions 22 

outdoor  and  indoor  remedies 22 

Spraying  against  woolly  white-fly 71 

greenhouse  thrips,  experiments 56-57 

treatment  recommended 58 

Squash,  food  plant  of  Pentatoma  ligata 8 

Stenamma  fulvum  aquia,  nest  containing  Ceratopogon  stenammatis 27 

I Stiphrosoma  atrata  taken  on  loco  weeds 41 

Stored  products,  dry  vegetable,  food  of  Arsecerus  fasciculatus 64 

i Strophostyles  pauciflora,  food  plant  of  Apion  fraternum  (= griseum ) 30 

Sugar,  food  of  Armadillidium  vulgare 17 

Sumac,  food  plant  of  Euxesta  notata 39 

Syrphid  larvae  preyed  upon  by  Formica  cinereorufibarbis 74 

Telenomus  ashmeadi,  parasite  of  Pentatoma  ligata  and  P.  sayi 10 

Tephrosia  virginiana.  (See  Cracca  virginiana.) 

Tersesthes  torrens , biting  habits,  distribution 28 

Thrips  adonidum.  (See  Heliothrips  hsemorrhoidalis.) 

greenhouse.  See  Heliothrips  hsemorrhoidalis.) 

Tick,  cattle.  (See  Boophilus  annulatus.) 

eggs  eaten  by  Armadillidium  vulgare 17 

Metoponorthus  pruinosus 22 

Porcellio  Isevis 22 

trefoil,  common.  (See  Meibomia  [ Desmodium ].) 

Toads,  enemies  of  pentatomid  bugs 11 

Tobacco  stems,  fumigation  therewith  against  conchuela  on  peach  trees 14 

Tomatoes,  damage  by  Armadillidium  vulgare 16 

Nezara  hilaris 8 

Pentatoma  ligata  in  1905 7-8 

screening  against  conchuela 14 

Tritoxa  flexa,  habits,  comparison  with  those  of  Tritoxa  incurva 38 


98  MISCELLANEOUS  RESULTS  OE  WORK  OF  BUREAU IX. 

Page. 

Tritoxa  jlexa  on  onions 39 

incurva  on  Aragallus  lamberti , general  account 38 

Tucker,  E.  S.,  paper,  “New  Breeding  Records  of  the  Coffee-bean  Weevil  ( Arse - 

cerus  fasciculatus  De  Geer)  ” 61-64 

Tyloderma  foveolatum,  host  of  Eurytoma  tylodermatis 31 

Verbena,  food  plant  of  Heliothrips  hsemorrhoidalis 51 

Viburnum  acerifolium,  food  plant  of  Apion  hereulanum 32 

food  plants  of  Heliothrips  hsemorrhoidalis 51 

lentago,  food  plant  of  Apion  hereulanum 32 

Vines,  food  plants  of  Heliothrips  hsemorrhoidalis 51 

Walnut,  food  plant  of  Coleophora  carysefoliella 81 

Walshia  amorphella , injurious  to  loco  weed,  general  account 34-35 

Water  spray  against  greenhouse  thrips 57,  58 

Weather  conditions,  effect  on  sowbug  Armadillidium  vulgare 19 

Weeds,  food  of  Armadillidium  vulgare 18 

Weevil,  coffee-bean.  (See  Arsecerus  fasciculatus.) 

Wheat,  food  plant  of  Pentatoma  sayi 2 

White-fly,  citrus.  (See  Aleyrodes  citri.) 

spotted- wing.  (See  Aleyrodes  nubifera.) 
woolly.  (See  Aleyrodes  howardi .) 

Yucca,  food  plant  of  Pentatoma  ligata - 8 


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